If you have 8:30 p.m. dinner, you go to the 6:30 p.m. shows in the Walt Disney Theatre.
The folks with 6:00 p.m. dinner go to the 8:30 p.m. shows in the Walt Disney Theatre.
The shows last around 60 minutes. Dinner lasts around 90 minutes. So, in either case, you don't miss the shows, and you have about an hour between the show and dnner (or dinner and the show).