If you're right-handed, sit on the right side of the theater, according to this article.

Interestingly, they say the opposite is not true for left-handers. It doesn't say whether the effect really has to do with right eye, not hand, dominance.

The article says a fair amount of unconscious self-selection happens. I prefer to sit slightly left of center, and I'm right-handed but left-eyed. My optometrist says cross-dominance is much more common in athletes than in the general population.