You can user either component or HDMI for HD video but if you want HD Audio you will need to move to HDMI and have a AVR that can support it. For standard 5.1 sound you can use optical or coax. As Adam says don't waste your money on expensive cables, I use $10 cable from monoprice.com and they work great.
The hookup will be your ste top box to the TV by HDMI or component. If you use a sound system you will go HDMI to the TV and optical to the AVR or you can go HDMI to the AVR and HDMI from the AVR to the TV.
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The problem with the gene pool is that there is no lifeguard and the shallow end is much too large
2013 Noah RS