Yeah, Netflix seems to use Silverlight with DRM, and there aren't Linux-based stuff that works as reliably.
Personally, I think just using Windows gives more flexibility and you don't have to worry about the nuances of Linux - especially if you've got a spare Windows licence floating around.
If you're wanting to stream TV as it's being broadcast (ie anything that you'd otherwise watch on BBC, ITV, Sky1, Sky Sports etc), then strictly, you'll need a TV licence.
Please try to keep any discussion of this out of the thread, I do not want it deleted due to this kind of talk.