Throwing a re-install at Windows XP should be an option of last resort.
Have you tried running a repair operation on Windows XP? First, at the
Windows Desktop, press F1, and search under 'Repair.' Read up on it. Boot
from the Windows XP CD and run a repair operation. This may do the job you
want.
However, if you re-install over an existing Windows XP, you will not lose
any files. You should, however, make a full system backup at this point.
Back up your files to either tape or writable CDs.