Resolved Computer won't boot after using "Registry First Aid"

I know, I should have known better, but the damage is done. My registry was bloated because I had been moving files around my computer from one partition to another, sorting them out, using sub-sub folders etc. "Registry First Aid" (Rosecity software) found over a thousand errors!!! and I let it make safe changes which were dutifully recorded in .reg files. So now I have a bunch of .reg files but no way to re-place them in the registry, as somewhere along the line a wrong change was made and WindowsXP C: won't boot. I have got another, backup WindowsXP D: on a 2nd hard disk but haven't the faintest idea how to use the saved .reg files to repair the registry on C: (which is still the drive letter of the unbootable OS) .
Registry First Aid is supposed to have made a full backup of the C: registry, but I don't know where I'd find it and, let's face, I haven't the faintest idea how to deal with a registry of a WindowsXP C: partition on disk 1 when I'm running in D: on disk 2.
Any kind of help would be appreciated.

 

Have you tried booting up with F8 key into safe mode?

Look in your Help file
Re4store registry from .reg backup files
or
Restore registry from a full backup


Contact the support desk at reg1aid@rosecitysoftware.com for more support.

Dick

 

Another option while in Safe mode, would be to try a System Restore. System Restore helps you restore your computer's system files to an earlier date when everything worked correctly. It's a way to undo system changes to your computer without affecting your personal files, such as e-mail, documents, or photos.

 

Thanks for your suggestions, the problem is I can't boot up at all, full stop, no safe mode option whatsoever, I'd tried all those F8 options.
I'm sorry for the delay in answering but I've been having trouble getting onto this site and now it's time for bed. So I'll see what I can do tomorrow.

 

XP's No-Reformat, Nondestructive Total-Rebuild Option - Fred Langa shows you how to completely rebuild, repair, or refresh an existing XP installation without losing data, and without having to reinstall user software, reformat, or otherwise destructively alter the setup.

 

Thanks SpywareDr. Brilliant idea, but again, no joy. I never got the chance to choose "Repair" but instead was offered to choose between all 3 partitions on that disk. So I thought I might have taken a wrong turn somewhere, but no, again choice of 3 partitions on disk. All right I thought, lost for lost, let's try the 1st choice, the bootable one that won't boot, maybe I'll be given the choice to repair on the next screen. Nope, I now have 2 Windows, one bootable and one Windows.0 (the f*cked up one), not quite what I had intended. Never mind, let's try and learn from our mistakes: no more registry cleaning!
I still have a slightly older image file of that partition (on a different hard disk), I'll try and use that one. Tomorrow! Enough for today!
I'll report back when I've achieved something. Thanks anyway.

 

There's obviously something wrong with my Windows XP Pro SP3 cd, I've tried it again on the other hard disk D: partition, no go! I then tried my first XP Pro (no SP) on my old PC that I only keep for emergencies (it still runs win98, has a floppy disk drive and is useful for playing with Dos and old, non XP compatible programs). No problem, I got the Repair option just like Fred Langa said.
I've reinstalled my 4 months old image, so no much is lost, especially as all my documents and setups of program are on separate partitions.
Thanks for trying to help.