Multimedia computer

Hey guys! I am upgrading my gaming PC, so instead of selling or stuffing my older pc in some corner, I've decided to turn it into change out some parts, hook it up to my tv, and use it for DVDs, Netflix, and Nintendo emulators. I plan on stripping out my hard drive and replacing it with a smaller one, adding some controller adapters, swapping out my crappy optical drive for a blue-ray drive, and adding a soundcard. I also plan on taking out my H100 and using it in my new computer. But before I start buying things, I have a few questions. (1) When playing DVDs on my desktop monitor, I noticed the quality wasn't all that great. WIll that improve when I upgrade optical drives? (2) What are some good controller adapters for N64/Gamecube/Wii? I plan on modding them into my case, so hopefully then can connect to my motherboard, or something like that. (3) Whats a good sound card? I've never really played around with them, so I have no idea what to get. I think the room I'm using is set up for surround sound, but I'm not sure on the specifics of it (it was installed when i moved in).  I dont know the price range for a good sound card, but I want something high quality.

 

In case you need it, my build:

CPU: Intel i5 2500k

Graphics Card: EVGA GTX 570 2GB

TV I'll be using: Samsung 40" 1080p 120Hz LED-LCD HDTV w/ 240CMR UN40EH6000F

Mobo: MSI P67A - GD80

Memory: COrsair Vengeance 8GB (2x4GB)

Storage: I'll be taking out my old one and putting in something with about 250 - 500 GB