XP Repair (non deleting) hangs at 2-minutes /...

Question

I recently had a problem with my PC. XP pro kept rebooting by itself. The system has ben working fine for 12 months. I tried to repair by non deleting as I did not want to lose my HD data. This led to other problems but also the root of the problem - faulty mem chip. I have since installed another drive fully installed XP pro with out problems. However I now wish to return to my original HD. This I did but when I tried to clean it up by repairing XP it now hangs at the 2 minutes / saving settings. ANy reboots force it back to reinstall by telling me to place XP cd back into drive only to start the whole process again