If you're watching in HD on a 42" (and possible speaker system), it'll be better than the theater. You can pause to hit the can and there won't be some needledick checkin' his cell phone. As someone mentioned, most of the movie is in a "stage" setting. There is very little action that would create any sort of "ah" factor.
I do have a similar set up to that, I also have projector ability if I wanted to do it that way, which is probably what I'd do. I think I'll save the money and red box it.
