If the tv has red/white audio out sockets then you could use these but it wouldn't be proper dolby digital, the z5500 would have to process the signal to achieve 5.1 sound.
If you only want home cinema for DVD's/Games then just use the optical/coax from the dvd player or console.
I think you'll need some sort of adaptor to connect the red/white leads into the z5500 pc input socket.