Hey, i have a question for you guys..

TV: 37'' Olevia LCD TV // XBOX360 Elite // PC has augigy SE card

If i have my xbox 360 connected via hdmi/red/white rca to my tv, as well as my Comcast digital hd cable connected to my tv... could i just run the optical out/or coax out(which one is better?) from my tv directly to my Z5500 and it all be controlled through that one optical/coax in ? And then just plug the regular wires directly from my z5500 to my pc ?

Or is there a better way to do this ?

... could i just run the optical out/or coax out(which one is better?) from my tv directly to my Z5500 and it all be controlled through that one optical/coax in ?
I doubt it very much, though I didn't look up your TV specifically. Most TVs will not route external audio to their digital audio outputs. It's too bad, because then we could do without receivers and use our TVs to switch among digital audio sources.

Just another note. Even if your TV does output audio over the optical output, it will most likely be stereo for any input. The TV usually only outputs Dolby Digital for the internal ATSC tuner.