[macojoe]

well now you have two op systems, you need to delete one not to confuse the computer.
Thats easy, just put new drive on as primary drive C Drive, * then delete XP from the old drive, that will free up the space you need to defrag.

I would still back up all files either by moving them from one drive to the other, or by burning them to CD's *Then Format C:, Fdisk, then move all back.

Good luck!