Here's my 2 cents worth...

Buy the optional cable for your projector to do HDTV...this is sold as an epson product....just your average HD15 D-sub to 3 RCA breakout cable may not work.

Get the transcoder for your DTC-100 I believe it's around $150.

Run HD15 from DTC-100 to the transcoder, then run the component outputs from there to the receiver.

Run your prog-scan DVD component output to the other component input on the receiver.

Run the component output of the receiver to the special cable on the Epson.

Run the various outputs on your other equipment, cable box, vcr, game system, etc. to the receiver's respectable inputs, take the outputs from that and run them into the composite or S-vid inputs on the projector.

Since the projector only has 1 component inputs, which is shared with the VGA input...you can'e do as RUDDY2 said, so you'll need the transcoder. But since I'm not familiar with the DTC-100, and don't really want to be...it might have the ability to change the output from VGA to component. You could then get by without the transcoder.