2 copies on 1 partition?

I recently FUBARed my main instalation of windows XP on my only computer. Basically the only thing that works is internet explorer and file explorer. All other applications say "the application failed to start because the settings are wrong or some bs..." which means I corrupted a lot of .dll files I shouldnt have. I need to burn stuff to DVDs so that I can format and reinstall windows again, the only problem is that no burning software will run, and XP pro doesn't support burning DVDs by itself (as far as I know, I cant get it to do it.) I can't install any new software because the installation program shows the same error.

I have plenty of room on my hard drive, a good 200GB. I want to install another copy of windows onto the same partition so I can install dvd burning software and save all my stuff( I cant make another partition of free space without deleting all data on the old one AFAIK) From what I've researched I think that windows will add a .0 to the end of all system folders and files when you install 2 copies on 1 partition (windows.0, documents and settings.0, program files.0 etc...) I could then choose to boot the good copy, install the dvd software, navigate over to my old stuff and burn it, then format and install clean.

Ive done this before when I was like 12 on accident because windows xp kept locking me out after the 30 days needed to activate. I ended up with like 6 copies of xp on 1 partition that ran fine untill I ran out of HDD space, but I dont remember how exactly it did it and if it overwrote anything. I honestly had no idea WTH i was doing  

I do remember I had options right after POST that asked which copy I wanted, and thats what I need. I just want to make sure I can do the same again without overwriteing anything or deleting anything. Also, I dont want to get a error saying I dont have permission to access the my documents folder. I think I remember that being a problem, that I couldnt get to my documents folder on 1 instilation of xp from another instalation without getting a permissions error. I really REALLY need to save all this stuff so if anyone knows if this would work or has a better idea please speak up!

Thank you!!!