We LOVE GG! We have another ADR here in Sept!
Like pp stated it does rotate very slowly. In fact if you really aren't paying attention to the walls/decore/scenes from Living with the Land ride you wouldn't notice it.
The characters spend plenty of time taking pictures and signing autographs. We thought the characters would be hit or miss with just adults but they were awesome! Chip and Dale kept trying to steal our dessert. Mickey sat with each of us in the booth for some great photos! Pluto wouldn't leave my mom's braids alone.
The food was basic. It wasn't anything too extreme where I couldn't pronouce it..

. To us it was familiar food that we eat at home...flank steak, turkey, some fish, salad, bread.
We have sat at both top and bottom spots. I thought both were about the same, no strong opinions either way.
I think your 4 year old will enjoy GG--and I think you might enjoy it too! Hope you have a wonderful trip!