Pay attention to the specific auditorium the box office assigns you. See if the movie plays in multiple auditoriums and chose the best one. See movies when they first come out for the best possible auditorium. Watch the movie on the week of release to get the best auditorium. Waiting results in smaller auditoriums, fewer show times, and a greater chance of discovering the ending.
Theaters place popular movies in the largest auditoriums.
Generally, attendance levels diminish as more patrons see the film. So watching the movie when its first released usually gets you the biggest auditoriums. If the movie you want to watch doesn't do very well during the first week of release, be sure to watch it immediately. Theaters tend to drop these films quickly. When deciding on which theater to watch a movie in, look at the sound designations.