I have a Compaq Presario M2512AU. Now I'm unable

Use your restore disks!!!!!!! If you do not have, purchase from Toshiba. OR just do a clean , new install of XP and other programs.

Preforming a system recovery to return the computer to its original condition may be necessary if the operating system is damaged, or the hard drive is corrupted, or the computer is infected by a virus.

___Also look this> HP expanded the battery pack recall on May 19, 2010. Click here to validate your battery. Performing a system recovery removes all software and files saved to the hard drive, reinstalls the original operating system, and then configures the settings for the default programs. Since the merger of Compaq and HP, several different recovery tools and processes Names for these tools include: Recovery Solution, Recovery Manager, F11, Recovery Disc, Driver and Application Recovery Disc, Roxio BackOntrack, Microsoft Backup & Restore. have been provided for recovering notebook PCs to their original operating condition. To help you select the correct recovery process, the table below identifies the different models, the time frame when they were produced and sold, plus the originally configured operating systems. Click on the name of the document in the right column for detailed information. Choose the Correct Recovery Process for Your Notebook Notebook description Recovery procedure information HP and Compaq Notebook PCs and Mini PCs shipped with a Windows 7 operating system. Recover Windows 7 Operating System Using HP Recovery HP and Compaq PCs using the Microsoft recovery feature for Windows 7 instead of an HP solution. Recover Windows 7 Operating System Using Microsoft Windows Backup and Restore Presario, Pavilion, and HP Compaq Business PCs shipped with a Windows Vista operating system. Recover Windows Vista Operating System Using HP Recovery HP and Compaq PCs using the Microsoft recovery feature for Vista instead of an HP solution. Recover Windows Vista Operating System Using Microsoft Windows Backup and Restore HP and Compaq Mini with Windows XP using the HP solution. Recover Windows XP Operating System On Mini Notebook Using HP Recovery HP and Compaq Mini with Windows XP using the Roxio recovery feature instead of the HP solution. Recover Windows XP Operating System Using Roxio BackOn Track HP and Compaq Mini with Mobile Internet Environment (MIE ). Recover Windows MIE Operating System On Mini Notebook Using HP Recovery Presario, Pavilion, and HP Compaq Business PCs manufactured and sold in 2006 or later . Recover Windows XP Operating System Using HP Recovery (2006 or Later)

Presario and Pavilion PCs manufactured from 2001 and 2005 . Recover Windows XP Operating System Using XP Operating System Discs (2001 to 2005)

And

Recover Applications Using Drivers and Applications Recovery Disc (2001 to 2005) Pavilion PCs with Windows Media Center edition of XP manufactured from 2001 to 2005 . Recover Windows XP Media Center Edition Operating System on HP Pavilion PCs Using HP Recovery (2001 to 2005) Compaq Presario PCs supplied with a Compaq Recovery CD and manufactured from 2001 to 2005 . Recover Windows XP Operating System on Compaq Presario PCs Using HP Recovery (2001 to 2005) Omnibook and certain Pavilion PCs manufactured pre-2001 . Recover Windows XP Operating System and Applications on HP Omnibook and Pavilion models Using HP Recovery (Pre 2001)

The problem maybe a loose electrical connection with the RAM modules and hard disk. Re-seat the RAM modules and the hard disk.
If the problem persists then the hard disk maybe faulty.
To test the hard disk, remove the hard disk and connect it to an USB hard drive adapter and connect it to a working computer's USB port. If this computer has trouble seeing it as an external hard drive and unable to open the folders and files then the hard disk is faulty.
Then the hard disk needs to be replaced in the Compaq and Windows XP needs to installed on the new hard drive and the device drivers and programs.

To successfully install the drivers in Compaq Presario C785TU Laptop with Windows XP operating System
Please follow these steps. Open this link and download ..

http://saysprasad.wordpress.com/2008/09/11/compaq-presario-c785tu-drivers-for-windows-xp/

What do u mean by unable?

You need to download the drivers from the Compaq/HP WEB support/download page. Make sure you select your model laptop and the XP Windows version of the drivers you require and install them.

Use this link to download the drivers
http://h18000.www1.hp.com/cpq-country/cpq_support.html

Here is the webcam drivers for that modelftp://ftp.hp.com/pub/softpaq/sp35001-35500/sp35414.exe
Here is the page that I found them on and others that you may need http://saysprasad.wordpress.com/2008/12/08/compaq-presario-cq40-108tu-drivers-for-windows-xp/

Here the driver download page of ur Compaq :
http://h10025.www1.hp.com/ewfrf/wc/softwareDownloadIndex?softwareitem=ob-31530-1&lc=en&dlc=en&cc=my〈=en&os=228&product=1841950

The Compaq Presario 5000 is not powerful enough to run Vista so XP is your best bet. I assume you have the standard 512MB RAM which will be fine for XP Once you outgrow that you'll need to go for more powerful hardware. By that time the new Windows 7 should have been officially released.

plz send me c772tu sound drivers