I recently worked on a computer that had a badly corrupted registry (took me
a long while to determine this because two different blue screen errors
pointed to RAM as the primary cause of the problem).  

Anyway I slaved the HDD from this computer into a working computer and
copied the registry files from Windows/Repair to System32/Config.  I then put
the HDD back with its rightful owner and booted into Windows.

The registry and/or Windows installation was so corrupt that I could not
access it via the Recovery Console and I could not attempt a repair
installation using an XP CD.  I would get a BSOD in both cases when either
program attempted to access the Windows installation.

Anyway here's what I'm interested in learning.  Are the original registry
components(Default,SAM,Security,Software,System) married to each other?  If I
attempt a repair installation of XP I get all new Windows system files but
retain my user and program information.  How can I accomplish the same thing
by playing around with the registry components?  

In other words could I take the repair Default,SAM,System,Security and pair
it with the original Software?  What combination of these components would
allow me to do what I want (salvage the installation without doing a repair)?

Thanks a lot for the info.   At this point I've already lost a ton of time
so I replaced the original registry components with the repair components
(had shut down system restore because I was virus hunting) and have begun a
repair install of XP for good measure.  I'm more interested in learning for
next time.

Thanks,

PO