In firefox, copy following directory: C:\Documents and Settings\Your name\Program files\Mozilla\Firefox\Profiles There are folders with the different profiles. Just make a copy of yours somewhere. And to restore it, copy the folder in the same directory, and edit profiles.ini, which is located one directory above. You just have to set the path to your profile folder right. Then restart FireFox and you're done.
thats nice to know..for soem reason my FF wigged out last week so i had to unistall and reinstall again.I had all my bookmarks exported so that wont a big deal..just all my addons and remembering passwords...