Why do you want to run component to your receiver and then to the TV? Usually people do that only because they don't have enough inputs on their TV so they use their receiver to switch the video (and of course audio) being set to the TV. In the PX75/77U case, you should have plenty of inputs on the back for you sat box and DVD player.
Is your receiver Pro Logic or is it 5.1 (or higher)? If it's only Pro Logic, then you can run you audio/video through either HDMI and/or component to your TV, and then use the analog output on the back of the TV to run the audio back to your receiver. That way, one pair of audio cables and one receiver input covers you for all sources. Of course, this won't work if you are trying to preserve 5.1 audio.