If I understand your question, hooking up a HT receiver for surround will have no affect on your picture unless you get a receiver that has component video switching (like my Yamaha does) and you use the reciever for audio AND video switching, but I recommend side-stepping your HT receiver and hooking your video sources directly to your TV. Then, all you are doing is using your receiver as a sound processor. If your DVD player has an optical-out for audio, use it. It's only one cable so that makes it easy. You could certainly use the receiver for processing the audio from your cable box, and if I remember correctly, the cable box has separate audio-outs which can connect into the receiver. This way, if your receiver is off, you still get your cable box audio on your TV, but you can also get processed audio if you use the reciever.
I recently bought an HDTV and use an HDMI cable to connect my cable box to my TV. I am about to invest in a home audio system and am nervous to buy the wrong one.
Is there any particular feature I should look for as to not compromise my HD Picture quality?
Thank you in advance.

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