Probably be about 11 feet away. Budget, good question. I think I would like to know my options as money will not be a huge factor.
Best bang for buck IMO is a projector + 100" screen.
You have to a state budget eventually.
Flat panel with biggest size, best value is most likely a 65" S1 + pro cal, or do the best that you can with SM offsets. No gamma controls.
Give up 5" or 17% size, and get the greatest flat panel ever made in the history of mankind, a Pioneer 141/151/600m. It's the last that has been had for a steal lately. I have no idea what the rep of this retailer is, but here's a place:
http://www.avindemand.com/index.php/electronics/lcd-plasma-tvs.html?manufacturer=259
When you compare that 2.7k price tag, to $7,000 for the 141 at my local Magnolia, you get an idea of how good the pricing is.
The one performance feature you are missing is CALcontrol ISFccc, but you can have the patch installed. Here is a list of calibrators that can do that for you, and then use it accordingly.
There ya go:
http://www.controlcal.com/forum/showthread.php?t=486