Hi gadget,
As far as the sound is concerned, it really depends on what equipment you alredy have. Personally getting a creativelabs 5.1 Live should do the trick for you (about $40). Please check this other thread of mine with info regarding this card:
http://yabb.jriver.com/interact/index.php?board=9;action=display;threadid=20722Then if you already have a good receiver and speakers, you'll be set. Otherwise, get your hands on a 5.1 PC speaker system (about$70 and up.) This will definitely make a nice change in overall sound quality.
As far as the graphic card is concerned, all you need is to have an svideo output. Well actually, that's assuming your TV is a regular one and not an HD one. I use an ATI Radeon 8500 (quite outdated now) and it works flawlessly for me. So anything newer should work just fine.
I'm not familiar with getting pictures and sound wirelessly directly to a TV set/ stereo. But if you have a 2nd pc and a wireless network, it's very easy:
On the server (bedroom) just do start:all programs:j river: Media server
Then click file:start sharing and you're set on this machine.
Now go to your lounge PC and start Media Center, File:Library:find media server. That should be it!
Hope this helps,
-Cascius