You don't really need Windows Media Center Edition to use a TV Tuner Card. I'm using (or was) using Windows XP Pro. The reason why it states that it needs Media Center OS is because of it's native support for media decoders. If you have XP Pro with SP2, you're as good as gold. Works great. Yes, it has built-in hardware MPEG-2 encoder on the tuner itself so it doesn't rely on main system resources too much.
It looks like a great card, but no remote. But that's ok though. We're like next to the PC anyways when we watch TV