What I want to do is save the registry and then be able to reinstall it at a later date (without subsequent changes).
I think there's just a couple of files I would need to save, but I don't know which ones.
Anyone?
Thanks in advance.
Read all about it!
http://home.adelphia.net/~bobstur/misc/w98regbu.htm
Hope that helps! 
That's about what I was thinking. Here's some things from the article that I was concerned about.
It explains how to make a backup, but it says windows does this daily when you re-boot. I typically install a new program and run four or five re-boots to test it out. It also implies that you don't always get all the backups to choose from.
New Q: It seems like the applicable files are system.dat, user.dat, win.ini and system.ini.
Can't I just copy these to another directory (or maybe even a floppy) and label it - Registry before I installed Program Y. Then re-copy them (From DOS) to the windows directory when I want to re-store the registry.

?