We did the Sunset Grill in December, it was woody woodpecker and Scoobey, The interaction was great, we couldn't get woody to leave!! The restaurant was basically empty and we enjoyed the food.
I'm pretty sure all 3 hotels have a character meal. I know there is a phone# for dining. (which I can't find) but I am sure they will be able to help you. As far as any character meals in the parks, I couldn't find any.