I agree with a lot of the above posts. I currently use a Denon receiver (great) and Boston Acoustics speakers (meh), but have positive experiences with Pioneer in the past. Haven't tried an Onkyo or the Polk/Klipsch speakers, though. Check cnet - they're really good at this stuff.
Also, as far as I can tell, wireless only helps in the initial setup. If you're willing to spend an afternoon stringing it all together, I wouldn't bother with it. Of course, I've never used a wireless setup, so like all other things I'm probably speaking out of my ass.