My home theater consists of a mid-range 1080p projector giving me 110 inches and a mid-range 5.1 Bose, driven by a Mac Mini. By far and away not the most impressive home theater in the world... but certainly good enough for most viewing -- particularly when you consider that I also have seven kids, one of whom is autistic and prone to noisy behavior and to leaving his seat frequently, and on top of that, my best friend also has four kids. So even not taking into account extended family, I would absolutely go for early release to home in a heartbeat. The number of viewers in my core group alone would make such a system pay for itself after only a few kids' movies, and occasional adult movies with friends would be a not-terribly-difficult splurge, particularly considering how expensive theaters have gotten. So even with a moderate upfront cost, as some of the options have suggested, this would still be a complete no-brainer for me.
That said... I would still go to the theater with my wife, on occasional date nights. You have to get away from the kids entirely for a little while every now and then, or you'll go stir crazy!