Garden Grill without a doubt. They bring the food to you and the restaurant rotates through the pavilion so the scenary changes. The flank steak is way good and we had some great character interaction.
We have enjoyed Chef Mickeys and are doing it again on our upcoming trip. We found the characters to be fun and the selection of food was good for all of us. We haven't done the Garden Grill yet. It is a buffet, however, and not a sit down dinner like the Garden Grill (if that makes a difference to you).