Connection of HD TV Issues

Question

I have a new Samsung 5076 DLP HDTV, a Motorola DCT6200 High Def Cable Reciever and a Bose 3-2-1 Series II Home Theater-DVD. How do I connect this so I get high definition?
I am using Y Pb Pr Component connections. I get a 480i picture on the screen. It will not show a 1080 signal.
What cables do I need to purchase to be able to get maximum audio and video from this system? And how do I hook it up? DUH, you have a real novice here on this one!