Each trip everyone gets to pick 2 meals they really want to do. My one son always picks SciFi and Le Cellier. We started going there because they had steak on the kids menu and he loves the cheese soup. Now he's a "disney adult" and gets the adult DP, but still wants to go to Le Cellier. The other son always picked Chef Mickey and Whispering Canyon Cafe. Last year our "new" place was Teppan Edo....and now that's his new favorite, first choice for this trip.
The rest we try to mix up everyone's favorites with at least 2 new places. We're trying the Grand Flordian Cafe and The Brown Derby this year.
My must do, and my mother's when she joins us, is Wolfgang Puck Express. In fact, I think my mom would be happy to eat every meal there so she could try everything on the menu.
regards