This is one of the best TV Tuner cards you can get and it's a very well known and reputable brand.
It supports both Analogue AND Digital TV, so you get the best of both worlds. It even Tunes FM radio!
It's a PCI card, but it fully supports XP and Vista, both 32bit and 64bit versions so it's pretty future proof. It'll work with Microsoft's Media Center products
Comes with PowerCinema (worth quite a bit on it's own!) as well as all the cables and leads you'll need to connect it up to just about anything (you might want to get yourself a better TV aerial, though, if you want good Digital reception), can even take component (That's Red, White and Yellow leads) so you can even plug in most of your consoles if you like.