Start WinXP in SafeMode(F8)then see do the Normal ERROR checking then run Disk defrag...If that doesnt work then on restart go back into Safe Mode then you can get to the Restore Utility and try resetting the restore Point Back...If this doesnt work then you need to wipe out and re-install XP...You might be able to try and REPAIR windows...Everybody has pretty much hit it on the head...At worst Take the hard drive out and Put into another machine and Grab the Data by useing GHOST and then Format that Puppy and start over....