But the only audio out on my TV is optical so how could that be?
You definitely won't have ARC on a 15 year old receiver. That was part of the HDMI 1.4 spec and has only been out for a couple of years. You could probably teach the VT60 remote some of the receiver commands so it will function like a basic universal Remote. That's probably. Your best bet. Short of buying a new receiver of course.