System Restore Alternatives

I have Windows 2000 installed on a 433MHz machine (yes, it's ancient). Due
to its being only a 433MHz I installed 2000 instead of XP Professional
because I figured 2000 was a better match to the machine's age, wouldn't
"overwhelm" it as much as XP Pro would, especially by the time you do SP2 or
whatever the latest service packs & updates are & everything.

Anyhow, I do realize that 2000 does not have "System Restore" which is one
XP Pro feature I love--if I install something new and then find it it's
spyware city, I can easily get rid of all remnants of it using System
Restore. (My wife loves to download games & install them, and often-times we
find out it has spyware & other junk on it, and at that time I'm quite
hard-up about getting totally rid of all remnants of it--I go through
considerable pains to get my computers as "clean" as possible so that their
performance isn't compromised.)

Since Windows 2000 doesn't have this, what are other options? I do hear of
people saying to backup the registry, but I get confused about how to do
it--some settings in doing this results in a file that's many megabytes in
size (like 30-70 megabytes or something)--isn't that awfully big for a
registry file? Also, wouldn't that still leave "remnants" of an undesired
program behind?

I did find this KB240363 article about it, is this what I am supposed to do?

(I also found this at Google where 3rd party programs are mentioned: