Whats a good sound system for my TV/BD set up?

[Mr.Sparkle]

I want a pretty nice sound system, not sure if I want 7.1 or 5.1, since I don't currently own any movies that support 7.1 (though I'm sure if I got a 7.1 I'd go out and buy one). Anyways, my room is fairly large, nothing crazy, but it's attached to the kitchen so over all it's pretty big, it also has a fairly high ceiling. Oh course I want it to support HD sound and all that jazz, I have a 50" Panasonic Plasma HD TV (don't know the exact model but I bought it a little over a year ago) and a Samsung Blu Ray player, again don't know the model but I bought it a little over a year ago. The room is already wired for a surround sound system so yeah what should I get, also where is a good place to buy one, I don't want to get played like a schmuck at Best Buy or anything.