First -- consider going to a matinee instead of night-time showing. Tickets can be as much as 30% cheaper... And you can always have dinner AFTER the show.
Or, join a theater chain frequent movie-goer club. They're free to join and you'll get reward points for every dollar you spend on tickets or concessions. You can use those to save money on future trips to the movies.
If you're a member of Triple-A, you can buy Regal or AMC movie tickets online or at Triple-A offices in bundles of ten. And speaking of concessions, some chains offer snack deals on certain days -- like dollar candy on Mondays or free popcorn on Tuesdays.
Regal/United Artists also offer free refills if you buy the really big size popcorn or soda.
Here are some links to help you take advantage of these deals -- and still get out to the movies.