Edit: The Samsung HW-K950 has 500 watts, not 250 like I said in the discussion. My comment about the wattage not implying quality still stands though!
There are so many different kinds of cables, it can be a nightmare trying to decipher what you need. HDMI, digital optical audio, coaxial, analog, component, RCA are all cables that could be used in your home theater configuration. I’ll go through the ones that you’ll likely use and leave the unnecessary cables out of the conversation.