i am running xp on a dell desktop and when booting has bsod stop.  i tried to use repair console, but won't accept  correct administrator password.  i tried bart pe to repair and found windows\system32\config has
o bytes.  is there any way to repair this?  any help appreciated     thanksYou can try a repair install. Boot to the XP CD and choose the SECOND repair option, allowing XP to install on top of itself. After completion you'll need to go to Windows Update and download & install all updates (except for hardware & driver related updates, which should never be downloaded from Windows Update - only from the OEM websites). Here is a clear tutorial on how to perform a repair install: http://www.geekstogo.com/forum/topic/138-how-to-repair-windows-xp/

option 2 doesn't work.  when i get to the eula agreement i press f8 to agree and the system locks up and i have to reboot.  where is the reg.bak stored so i can try that route?  i run KEY finder and it list the computer but with no information.  it's a dell with oem windows install so this could be one problem.  i can format the drive to intall a fresh copy, but i need the windows key so i won't have to purchase another os.  any suggestions?  any help would be greatly appreciated.  it's my brother's computer and he won't buy another os.    thanksMore information brings more help.
The exact model number of the dell is needed.
Dell has more models than VANITY Fair Magazine

Was the PC installed with OEM XP by Dell?
In some cases the CD you can purchase from Dell for a reasonable price.
The Dell should have a COA on the back, SIDE or under the chassis. That product key may not work does not work on a retail version of Windows XP.**

You can 'slave' the hard drive to another PC and backup the data to a backup image, if there is enough free space on the spare PC.. Just in case. If you have to install a fresh copy, some data can be recovered from the backup image.

** REFERENCE: from the Dell site.
http://en.community.dell.com/support-forums/software-os/f/3524/p/19324139/19665126.aspx