I don't use WinME, but my roommate does. He loves that system restore feature [cracked gamez can mess with your system :D]. From seeing what it can do, I think it would be a great addidtion to Win2K.
Another option, is Norton's Ghost, which, if I had the room, I would have made a Ghost of Win2K right after I installed it, so I didn't have to go through a complete reinstall if something does go wrong.
Those are the only two I have any experience with.
-bZj