I did the Polynesian Luau a few years ago and enjoyed it. Food is good and served buffet style. Each table sits about 10 people, so you'll be sitting with other people. The entertainment is your typical luau entertainment - Polynesian dancing and singing.
We prefeered it to the Disney one. like others said typical luau dancing etc, and they get all the children up on the stage to teach them to Luau, and the food was excellent