Hello
If you have saved (backup) your files (Documents, Pictures, Music, Etc) then you can do the following using your reinstall disk;
1.) Boot off of the Installation disk (Windows XP Disk)
2.) Read through the statement that appears during the disk booting
3.) Select delete partition
4.) After deleting the partition, it will ask you to create another, select new partition
(this will automatically assume the role of C:\ drive
5.) The select format the new HDD partition (after the formatting it should automatically start installing Windows XP
Just follow the instructions from there.
Keep in touch.
