Just wondering how difficult it would be to change the grey color on application windows in OSX to a different color for each application? I have tried an app called CrystalClear Interface that meant to do this but it messes up a few things on my system. Is there some other, fairly simple way? I am running Snow Leopard and have pretty much no experience of programming.
To answer your first question: According to what I've found (1,2,3), doing it manually is fairly difficult and requires some hacking around in your system files. You probably don't want to do this, given your experience.
This also answers your second question: A simple way to do it would be with an app such as CrystalClear.
If you want to try some alternatives, you should be able to find some via a few Web searches.