Ouch. Sadly I think you're damaged the OS too deeply for an XP Repair Install to fix it again.
Next time, make a copy of your system. Here's some freebies to get that done.
I have windows XP Professional on my Laptop CompaQ Presario C500, with 512 MB Ram and dual core processer. My windows XP freezes and showed back screen no voice, no mouse pointer and it stays and user accounts never comes.
I shut it down and different choices comes after restart, it restart perfectly in safe mode, in last good cofiguration, but never start in normal way.
I used msconf. utility to remove all the start up program, I remove all the services, but it never start normally.
I also used http://icrontic.com/articles/repair_windows_xp
repairing windows in 8 commands, but the same problem.
Hard disck check good
No virus, as checked by trend micro, kaspersky and symentic.
Can I revert it to original state, but I do not have the restorer point that much old, the last restorer point did not fixed this problem.
I have the original disk, I reinstall it as a last resort, if everything fail. Thanks for advice in advance.