Can I protect my file associations?

[Cerb]

So I wanted to watch a DVD, and had no way to do so. So I installed my copy of WinfastDVD (it was handy), and...it changed MPEG files to play with it. &$%@#*#!!!! That's one of those little things that pisses me off--at least ask in the installer! I'd have used MPC for the DVD itself if the audio wasn't messed up in it (no normal stereo track).

Is there any app out there that will warn me if I want to change associations, preferably by asking when something is trying to do it? And/or an app that can be easily used to just snapshot that section of the registry every day or two would do, as well (but it would need to have a nice UI for it, as technically regedit can do that...).