Ipod has gone into diskmode

iPod Symbol Meanings
The Apple iPod personal media player uses a set of symbols to communicate what's happening to the device: when it needs to be recharged or when it's experiencing problems.
Sometimes it's not obvious what these symbols mean; problems with your iPod may cause conflicting or confusing icons to be displayed.
Folder with an Exclamation Point

This suggests that your iPod can't read data stored on it.
Your iPod may simply not have enough charge in its battery to read its hard drive.
If recharging it doesn't help, you can try connecting it to your computer, then updating it with the latest version of the iPod's software.
If none of this works, you may have a dead hard drive; your iPod will need to be repaired.
Battery with an Exclamation Point
A battery with an exclamation point usually just means that your iPod needs to recharge.
Once the battery has charged up again, everything should be fine.
You can charge an iPod through a FireWire connection to a computer, but not if the computer is in sleep mode or switched off.
Third-generation iPods cannot be charged via USB 2; later iPod models can, however.
If you are having problems charging your iPod, try switching cables.
You can also try resetting the iPod by pressing Play and Select together (Menu and Play on earlier models).
If none of these methods help, your battery may need to be replaced.
Empty Battery
If the battery icon shows an empty battery, this means that your iPod is almost out of charge and needs to power up.
If you know that the iPod has been charging for a while, and the battery icon is still empty, you may need to update its software.
Older software can lead to a confused battery readout.
Wall Plug with Power Adapter
This means that your iPod needs to be plugged into an electricity supply while it updates its firmware.
You won't be able to do anything else with it until you do this.
Frowning IPod Icon with an Exclamation Point
A picture of an iPod with a sad face and x-ed out eyes plus an exclamation point indicates a very serious problem with the device.
In some cases, draining the battery completely then recharging and resetting the iPod can offer a short term solution, buying you enough time to back up your iPod's data.
The underlying problem will remain and is likely to get worse until your iPod is repaired.
Apple Logo
A brief appearance by the Apple logo when the iPod is reset or switched on is normal and nothing to worry about.
If the logo does not go away and the iPod doesn't boot up, there is a problem.
You can often resolve this by putting the ipod in Disk Mode and then restoring or updating its software; note that you will lose all data stored on the iPod if you do this.
If this doesn't work, your iPod needs specialist attention.
Do Not Disconnect
It is not safe to unplug your iPod when you see this icon. Wait till it goes away, then you can safely disconnect your iPod.
Spinning Disk Icons
The spinning disk and magnifying glass icon means that the iPod is performing a disk scan.
If you don't want to perform a scan right now you can re-set the iPod; you'll see a disk with a cross when you stop the scan.
If you would rather let the scan complete, you should connect the iPod to a power source as scanning drains the battery.
If the scan finds issues but can fix them, you'll see a disk plus an arrow.
If everything is alright, you'll see a disk plus a checkmark.
If there is a problem that the scan disk function could not fix, you'll see a disk plus an exclamation point.
Ipod shows RED X
http://support.apple.com/kb/ts1463
Resolution
Restore iPod from Disk Mode

• Hold down Select / Menu (to reboot the iPod)
• As soon as the Apple logo appears, hold down Rewind / Select until...
• ...you see a backwards Apple Logo.
• At this point, you will have entered Diagnostic Mode. It'll test the RAM, and then tell you to HIT PLAY TO CONTINUE. Hit 'Play'.
• You'll be in a menu that you advance by hitting FF (Fast Forward). Advance to the 'DISKMODE' entry.
• Hit 'Select.' This will put you into Firewire Disk mode. The screen should change to the familiar 'Do Not Disconnect' mode. At this point, connect it to the computer.
• Run the restore utility; it should now recognize the iPod and offer to Restore the factory software. Do so. You'll lose whatever's on it, but you'll avoid having to send it back in to Apple and pay them $49 or whatever to do basically the same thing. :-)

from: http://www.sharp-tools.net/archives/000240.html

Hmmmm try this link below they are some tools to help you do this, fix. http://www.copytrans.net/gettingstarteddoctor.php
How to fix the iPod
There are multiple ways to fix the corrupted iPod, though it’s not 100% gauranteed it will work coz chances of HDD corruption do exist.
- Restore method Try putting it in disk mode by holding the Menu + Center buttons until the Apple logo appears, then when it Logo appears, switch to holding Center + Play/Pause buttons until it says “Ok to Disconnect”. Then try formatting or restoring it and see if it fixes it at all. To get out of disk mode, reset your iPod by holding Menu + Center buttons until the Apple logo appears again. If this fails, proceed with the next.
- Disk management: plug in iPod > Right click My computer > Manage > under “storage”, click on “disk management” right-click on the iPod it shows. “Change drive letter and paths…” then change the drive letter to something different. Then unplug the iPod and plug it back in again. It should work.
- Driver Re-install -Plug your ipod into your computer, My Computer > manage > Device Manager and click on Universal Serial Bus Controller. Then click the plus sign and find the one with your device (it should say something like “USB Mass Storage Device.”. Right-click on that device and select “Uninstall.” Let the screen refresh. Replug your device from the computer, wait about 5 seconds then plug it back in.
- Formatting and Restoring Another way is to format the iPod HDD (and then restore) to remove minor disk errors that might have come over usage of iPod.
To proceed with this, you need a utility called HP USB. You can either google it or download it here. Format the drive as FAT 32 and then you should be able to restore it with no problem.
- Try CopyTrans Doctor Its a good software for iPod recovery and fixes. Guide available here.
If All of the above methods fail, probability of having bad clusters is high.
How to confirm iPod Hard disk has gone bad?
If you succeed in doing the quick format with the utility tool, and can now right click on Apple ipod in “my computer” and get the menu, proceed with this. Select the iPod in “my computer” right click >Properties > Tools > check disk. MAke sure you have the checkbox ” Attempt for the recovery of bad sectors” selected. Now your disk is checked for consistency. It will be checked in 2 phases. If it fails in any one of those with un-repairable message or freezes infinitely, then there is no solution, you would have to rush to apple to get the support. Else try the above steps again with the latest iTunes, it should work.

I solved this problem on my IPod 30G unit. When I would hook it into my computer (Win XP), ITunes would crash and my IPod would just keep rebooting. Even on it's own, it would play for a few seconds and completely reboot over and over. I suspect that part of the problem is that my battery isn't holding a good charge anymore so make sure the unit is fully charged when trying to use it. This may solve the problem.

If charging it isn't the problem, hook your IPod to your data cable and plug it into your computer. Press and hold the Menu and center button for 6 seconds until the Apple logo appears. Then immediately let go and press and hold the center button and the play button for as long as it takes. You'll see a checkmark appear and your unit will go into disk mode. The 'do not disconnect' message will appear. This is good. Shut down ITunes (if it is running) and go to 'My Computer' and open that. Your IPod should show up as a drive in your listings. Right click on your IPod icon and choose to format the drive. Make sure you use a regular format and that it is being done with the FAT32 file system. It takes a while but it will eventually finish. When it is complete, unplug the IPod from your system, wait a few seconds and your IPod should default to asking you what language you want. Choose your language and hook it back up to your PC.

If things work as they should, ITunes should pop up, ask you a few questions as though it was the first time you are using it and proceed to reinstall everything as it was before.

if you have an Apple logo stuck on the screen) try the following sequence of steps:

• Hold down Select / Menu (to reboot the iPod)
• As soon as the Apple logo appears, hold down Rewind / Select until...
• ...you see a backwards Apple Logo.
• At this point, you will have entered Diagnostic Mode. It'll test the RAM, and then tell you to HIT PLAY TO CONTINUE. Hit 'Play'.
• You'll be in a menu that you advance by hitting FF (Fast Forward). Advance to the 'DISKMODE' entry.
• Hit 'Select.' This will put you into Firewire Disk mode. The screen should change to the familiar 'Do Not Disconnect' mode. At this point, connect it to the computer.
• Run the restore utility; it should now recognize the iPod and offer to Restore the factory software. Do so. You'll lose whatever's on it, but you'll avoid having to send it back in to Apple and pay them $49 or whatever to do basically the same thing. :-)

Plug it into a wall charger if you have one, or back onto the computer to see if it will charge, as it might be a low battery issue.

If not, press and hold Menu and select/center, until the ipod reboots/resets, and you see the apple menu. Then your ipod should be working.

If it still does not, press menu+select again to reset, but right as it shows the apple logo/when you hear the hard disk moving (if you have a video/classic/one with a hard disk) move your finger from menu to play, while keeping your finger on center. This will engage Disk mode, where you can plug it into your computer and format the disk.

This will erase all songs/data. once you have formatted (to FAT32) through My Computer (by right clicking your ipod, and clicking format) Open iTunes and 'restore' your ipod, which will reinstall the firmware/software. For formatting, you can do 'quick format' if you want, it doesn't matter.

Hope this helps!

Hi! YOu need to disconnect your ipod from the pc.
Put the ipod into diskmode by following these instructions-
Before placing the iPod into disk mode, you should verify that it is charged.
Toggle the Hold switch on and off. (Set it to Hold, then turn it off again.)
Press and hold the Menu and Select buttons for at least 6 seconds until the Apple logo appears.
When the Apple logo appears, release the Menu and Select buttons and immediately press and hold the Select and the Play/Pause buttons until the Disk Mode screen appears.
Connect the iPod to your computer; the screen on the iPod will change and say "Do not disconnect

After doing this open latest version of itunes and then restore your ipod to factory settings by selecting it from itunes.

go to google and type in iTunes download. find one and download the new software. once you have downloaded it on to your desktop double click on it and it will say welcome then plug in your ipod you should be good from there... this is what i did

http://www.apple.com/support/ipod/tutorials/troubleshooting.html

Reset your ipod and then if you see apple logo hodl down center and play buttons. Then iPodi goes to diskmode, maybe your computer then recognizes it. 
You can try also disable a virus protection programs for a second, maybe some program is blocking ipod.

Start with these five simple solutions: Reset, retry, restart, reinstall, or restore http://www.apple.com/support/ipod.five_rs/

If that doesnt help drop me a comment.