Lee,
Do not be scared off by the Denon manual. It is more of a running joke over on AVS forums. There is excellent support over there for setting up the Denons. IMHO, all newer AVR's are hard to understand by mere mortals. ;\) In your sized room, with a sub, you should be happy with the M60's. In my large room, I felt the M80's did a better job of pushing more air to fill my space and hence sound fuller. YMMV.

Dave

"In theory, practice and theory are the same. In practice they're not."