G5 Powermac as home entertainment system?

Hi all, We are about to move house so i am thinking how best to set up the living room, I previously had my 42" plasma plugged into a sky box & for dvd's a Pioneer 5.1 home cinema system, I would like to Plug in a G5 desktop & use it for dvd's/internet/photo's etc do they all have optical out that i can plug in to my home cinema & will it produce 5.1 sound?, The mac will be secondhand & i don't have a lot of cash (about £350/400) is this possible & if so what's the best spec to go for.

Cheers

P.s Can you get a remote for it?

I know you can get remotes for iMacs- I own one myself, they play movies and work brilliantly for me! In fact, i would suggest buying yourself an iMac and attaching a projector to it. Then you would have use of the remote.

Oh, and it's definitely worth it - the new iMac display on projector is like sitting in heaven!