Hm. I don't use Fedora so I don't know anything about that, and I've never had any problems with the nvidia drivers so I never learned much about them, either. I learn most when stuff doesn't work.
So I'm just guessing that either you need to uninstall the drivers (even though they already are) before reinstalling or that you may possibly need to do something with your rpm database. I don't think the drivers pay any attention to that, but I'm not sure.
J-Alta-K, you really ought to start a separate thread for a question like that but, to try to answer your question, I doubt it, but it might well work on Xandros since Xandros and Linspire are both Debian-based (I believe). The likelihood of incompatibility is high, though, and it almost certainly wouldn't work with Mandrake.