Two rows of seating then.
Are the Definitive Technology dipole speakers, with rear firing drivers? If you plan on acoustically treating the front wall, rule out dipole fronts.
As for tower speakers, a sub/sat system has a placement advantage. The best location for a subwoofer is seldom the best location for the mids/highs.
And you lose the advantage of a sub having it's own amp.
Ideally you won't be carpeting the walls or ceiling, you will wood frame the walls, insulate the wall cavity, and drywall. Double layer of drywall possibly.
A further step would be acoustically treating the walls and a fabric finish.
(I would be taking 4DHD's advice over the Best Buy guy. I'd be thinking horns, or compression driver'ed speakers.)
I was going to suggest a DIY acoustically transparent screen using Seymourav's XD material. And leverage the fact that all front speakers could be hidden. Starting with 2.1 is fine but
3.1 might be a better choice. (You could build subwoofers as a budget stretcher.)
Movies and gaming and a good sized room makes me think SOWK's room, without the extra deep AT space, might be inspirational to you.
http://www.avsforum.com/t/1325369/sowks-home-theater-buildEdited by Tedd - 5/31/13 at 5:21pm