I heard that buying headphones(a good quality pair) is a really good option for playing FPSs b/c you can hear people coming better. Would I have to buy a sound card to get good quality sound? Or is it better to get like a logitech 5.1 surround sound with an Audigy 2?
If you're going to prepare for that new box you're looking at, I'd go with some speakers. Personally, Creative has some nice setups for a good price. I've bought their 4.1 speaker sets before (FSP1000, Inspire 4400), and they work great, both running around $60 when I got them. You'll pay around $100 for Creatives 5.1 set. The nForce 2 has a 5.1 soundcard integrated, and that's actually pretty good.