As mentioned previously, Scandisk isn't present on XP like in older Windows versions. "Error Checking/Chkdsk" is the new program that provides a disk check and can be run a few different ways, but I prefer to do it like this:
Open "My Computer", RIGHT click on the C drive icon, choose "Properties". When that loads, click on the "Tools" tab, then click on the "Check Now" button in the "Error Checking" section. When that little window loads, click on BOTH boxes, then click on "Start Now". A message will pop up saying that Error Checking will run after you restart the computer, so......Restart the computer. Error Checking will run automatically after the restart and it locks you out from doing anything until it's finished. It takes a little time to perform the task but after it's finished,(assume 30-60 minutes) it will restart into Windows.
Hope this helps.
Grif