If you still have your windows Xp install disk, you can run a repair install to replace any corrupt/missing files. You can also just put the XP install disk in the drive, and then
...you can repair your Windows install using the original install disc. Windows will prompt you to repair it and Windows will check each file and repair it. START, RUN, CMD and type “SFC /scannow.” It’ll do the same thing and repair whatever .dll files are damaged.
If you don't have your disk, I'll see if I can get a copy of an XP task manager when I get home.