Quick and Easy Question for some. Plz Help

I just bought a samsung 1080p ldc tv and I have an Xbox360 Pro at home. I was just woundering do I need any more wires for my hd experience. I have the a yamaha sound system and was woundering If I need any special wires. I am a little confused about the sound wires. Some friends told me I may need optical wires? I would like to get the best picture with my hd and good sound on my 5.1 surround sound speaker system. Any help would be appreciated :) Thanks