You are staying two-channel and just trying to migrate to a music server, right? If so, I'd suggest looking into something like the Slim Devices SqueezeBox. It has pretty respectable DAC's (they're Burr Browns, certainly more substantial than what is in the AppleTV) and it has a built-in display so you wouldn't need to have a TV on hand to operate it.

If you do decide to replace the Adcom gear with some home theater equipment, you might think about going with a pair of M2200's instead of a seven-channel amp.