Last February we stayed at the Poly and set aside one afternoon to visit the GF for lunch. We got some great burgers there at the counter service place. It was too chilly for us that day, but I highly recommend the outdoor seating here. I didn't love sitting inside because you are sitting basically in the arcade area. There's plenty of tables outdoors, though, and the view of the water and the atmosphere are great. We almost didn't find it though. You have to go down to where 1900 Park Fare is, then go outside and around the building to get there.
At the Poly, we had Captain Cooke's once for dinner, and ate it in our room. The food was good. I had the asian noodles (that is similar to what's served in Kona cafe) and DH had the pulled pork sandwich. There's a strong smell there, whether it's the cooking oil or burned flatbreads, I'm not sure. I'd only go here if it's a pretty day and you can sit outside. They have some outdoor seating, with views of the volcano pool. They have pineapple and vanilla Dole Whip available from a self serve machine here, if you like that it's a huge plus!