While Newcastle receivers are fine, the Axiom rep recommended it because Axiom is a Newcastle distributor. I'll preach love for Axiom as much as the next guy, but business is business.
Denon and Yamaha seem to be the most popular brands of AVR around here, but you'll find the gamut of receivers (and preamp/amp combinations) represented here. Denon and Yamaha make very good equipment and you probably can't go wrong with either. So long as you're not looking at M80's*, just about any name-brand AVR (Onkyo, Sony, Kenwood, Pioneer, JVC, etc) will do a fine job at running your Axioms.
For the size of your room, I'd recommend the VP150, but I'm not an expert. Don't forget that with movies your center does the bulk of the work in producing dialog, so don't skimp on it. You might want to play around with the Home Theater Wizard. It works pretty well.
The M22/VP150/QS8 solution is a common - and excellent - choice. Good call on the HSU subs. A whole lot of folks really like them and I've picked up feeling that they offer a bit more bang-for-the-buck than the equivalently priced Axiom model.
The only "problem" I can think of due to your room size that you'll need to deal with is the placement of the surrounds. Having an extra 11' of room behind you isn't a big deal. Actually, IMHO, having an open area behind your seating position is a nice bonus, as you can position the surrounds a bit behind you (I prefer them there, as I listen to a lot of multi-channel music), or even take the plunge into 7.1 audio. So long as it's ok to have the speakers on the walls in the "kids'" area, I don't see a problem. If it is, several forum members have QS8's suspended from ceiling hangers just behind the seating area, and that seems to work well for them.
If you've made up your mind to get Axioms, that's excellent.
If you're not completely decided, check out the 'Hearing Things' forum for demos. There may be someone in your area with Axioms willing to show off their system.
*M80's, being 4-ohm, *may* be a problem for *some* AVR's. Most midrange+ AVR's don't have a problem, though mine did.
