30 GB Ipod not shutting down

Slide the Hold button on the top of the iPod so no red mark is visible. Press the main menu button until you see a long list of options (Artists Albums Songs Extras......) use the scroll wheel to find the sleep press and hold the center button in or Locate the Play/Pause button on the iPod. The Play/Pause button is at the bottom of the wheel around the select button. Press and hold the Play/Pause button until the unit powers off, about three to five seconds. Press any button on the iPod to turn the power on.

Try pressing both menu and center buttons for 15 seconds and see if it reacts.
Remember to unlock the hold button ;)

Hope this helps!

try holding the center button and the menu button to hard reset it .. .it might work for you ...

Have you already attempted to force the iPod into disc mode before connecting the iPod to your computer? If not I would recommend doing now. If you can get the iPod to connect to your computer at this point you will want to restore it using the latest version of iTunes.

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" If you are having difficulty putting the iPod model into disk mode, set it on a flat surface. Make sure that the finger pressing the Select button is not touching the Click Wheel. Also make sure that you are pressing the Play/Pause button toward the outside of the Click Wheel and not near the center.
If you are still unable to put your iPod with a Click Wheel into Disk Mode, use one finger from one hand to press the Select button, and one finger from the other hand to press the Play/Pause button.

Press and hold the center button and the menu button at the same time. This will reboot your Ipod.

Hey check out this link it worked me.. http://inc0gnit0s.wordpress.com/2009/07/19/error-1439-while-trying-to-restore-or-sync-ipod-with-itunes/

First make sure your hold switch isn't on. It's on the top or bottom and slides back and forth. It needs to be switched to the left. Once it is to the left, here's how you reset:

You can reset your ipod by holding down the menu and select (round button in the center) buttons down for at least 10 seconds. You'll see an apple logo flash, that's when you stop pressing the buttons. It will shut off, then back on.

http://ipod.about.com/od/troubleshootingyouripod/ht/reset_ipod_vid.htm

Press both the center and menu buttons until the ipod shuts off (about 5 seconds.) it will then reboot itself and the problem should be fixed.

Try charging it?