The error message on the BSOD would have been useful...but...life goes on
So just what did you do to "redo" the O/S? Clean install? Repair install? Restore CD/partition?
Manufacturer/system model? Laptop or desktop?
Do you have a MS XP CD?
Can you run chkdsk /r from the Recovery Console?
Have you ran a manufacturer's diagnostic on the hard drive itself?