I'm hooking up my home theater in my new house. I have a 36" Sony XBR, Sony DVD and VCR. I got a deal on the RCA 2500 HTIB, 100w a channel plus 100w sub, total 600w. I put JBL in-walls for speakers and use RCA sub for now. The question is, everything is supposed to go into the receiver then into the TV, but I have cable TV that goes to VCR then to the TV. The DVD is hooked to TV by composite lines. When I introduce the receiver into it how will I get the cable audio to the receiver so it will play over the speakers? Is there a significant diference in picture by going to S-video to get into the receiver then to the TV in S-video instead of the composite I have now? Audio will be optic.