I would recommend Columbia Harbor House at MK. If you want a break, take the monorail to Contemporary or Poly. At CR, there's Contempo Cafe, and they have some tasty selections.
At Poly, ground level, there's Captain Cook's. It's OK there, but it has the Dole Whip if you like that. Personally, I like stepping in to the Poly just for a look around. There's a nice coffee bar, and sushi bar at 5pm, on the monorail level. And some fun shops to look around.
At GF, there's Gasparilla Grill, and it was OK, with some unique selections. Again, walking around GF is the draw there. Lots of beautiful decoration and art.