Be careful not to underestimate the importance of a good projection screen. It will be counter-productive to purchase am expensive, good performing projector and have your screen degrade the image. 3-chip DLP's do not exhibit the "rainbow effect".
Just by the seating distances you mentioned, a projection system is your best option. Say with a 120" screen. IMHO, the display system is the most important element of the home theater. Too bad it was prioritized so low... Under $2,000? The only possible solution at that price would be a 73"...
120hz processing generally doesn't work. More marketing fluff. If you're looking for bang for your buck, DLP is the way to go. Lots of choices. Optoma, JKP Samsung, Panasonic, BenQ, Runco... all depends on your budget.
Widescreen Review Some reviews may be somewhat technical for the average consumer, but you can be assured you will receive an objective, thorough review. The fact that they calibrate the display during the evaluation and report on it, gives you a more complete, and accurate, review for that...
What do you mean by placement flexibility? I would hope anyone that installs a projection system would tailor everything around the proper placement for the projector. Lens shift and zoom are helpful, but too much may cause optical errors such as chromatic abberations. Digital keystone...
DLP will be your best bet for fast motion. Screen size/type needs to be factored into the equation, along with price point. Lots of choices once you set your budget.