If you are running Windows 2000, Me, 98 or 95 and you need to backup your registry (regularly or just in case)...I would suggest to use the software in the following link....it works great....even better then system restore......it works for Windows XP and 2003 as well.
to download :
http://www.larshederer.homepage.t-online.de/erunt/
Learn how to use the software:
http://www.eggheadcafe.com/articles/20051101.asp
I'm sure this software will save some one's behind someday.
Cheers