Try the following web sites for troubleshooting suggestions:
Visit http://www.kellys-korner-xp.com/xp tweaks.htm and scroll
down to Line #48. In the right-hand window, click on
"Disk Cleanup - Compress Old Files Freezes"
Simply click on Kelly's fix, download the registry fix, then run it.
(Note: Disable your antivirus program before running the repair script)