A recurring discussion on this finds we can't move XP from drive to drive without a repair install. Hint? Type XP REPAIR INSTALL on google.com
There is no supported method to do what you ask and have it all work fine at the end of the process. If I were you I'd leave it be till you have time to reinstall XP proper.
I have XP SP1 on C drive and XP SP2 on E drive. I would like to keep SP2 and remove SP1. How can this be done.