I would also recommend Liberty Tree Tavern at MK from a pure fill-up perspective (and yummy food). We have 3 teenage boys and they had to be rolled out of there last week. It is their favorite place to eat in MK.
As a side note, we used to be much bigger fans of the plaza until the most recent menu changes. We also ate there last week and were told by the waiter that there would be menu changes again sometime soon, bringing back the main street burger, turkey club sandwich, and perhaps other items. You can get pretty filled up there too if you get a milk shake with the meal.