Saw both last year-HDDR and the Luau. Both were very good and my DS's ages 10 & 8 enjoyed them both. However, they requested the HDDR again for this year. It's funny with sort of corniness to it. I never heard my 10 year old laugh that much. When you first get there and get seated a photographer comes around for the family pic. There is already salad on the table to start eating. Next they come around with the fried chicken, which is "out of the world" and ribs in small metal buckets. The drinks by the way are in mason canning jars. They also bring out corn on the cob and baked beans. Entertainment is going on throughout while you eat. They do take a short 5 minute break here and there,but basically the show is none stop. At the end is the strawberry shortcake. They also come around with the "old washboard" to "strum" along with for the finale. It's really a lot of fun and I think your 12 year would enjoy.
The Luau was nice. The story was about families and traditions. My boys enjoyed the guy doing a dance with the lighted stick. They didn't care too much for the rest of the dances. Food and service was good.
Hope this overview of both helps.