Hard question.
1 The Blue Lagoon. My favourite restaurant for themeing and atmosphere and I've always liked the food. Pirates of the Caribbean is also my favourite ride.
2, Walts, an American Restaurant, Maybe my favourite for food. Get a table by the window if you can and enjoy the view of Main Street. When we ate there for the first time we were given a table outside on a warm summers afternoon, there was table seating downstairs then.
3. Silver Spur Steakhouse. Very good food, Wonderful themeing again.
4. Cinderella's Inn. I really liked this restaurant and I would put it higher on my list, but since Disney turned into a character meet and greet restaurant with the Disney Princesses, we've not dined there. Will look into it on a return visit.
5. Plaza Gardens. Always been very fond of this restaurant although I enjoy the other buffet restaurants, too Agrabah Cafe and Restaurant of the Stars. My favourite has to be a table service restaurant in Disneyland Park, but I've still not eaten in all the hotel restaurants, other than at breakfast.
We avoid fast food restaurants for the most part ( although we have tried some of them Toad Hall was good for example ) and go for the buffets.
Never dined in Colonel Hathi's Pizza Outpost, we walked in on one occasion and thought the themeing looked wonderful. Had Disney kept it a table service restaurant, which I think it was originally, called the Explorers Club, we would have eaten in there by now. I'm sorry that they didn't, dining outside on the restaurant terrace in Adventureland in the summer, with a good meal and a glass or two of wine, well I think that would of been very special, sitting inside or outside. If Disney had turned it into a buffet restaurant like the Agrabah Cafe, which was originally shops, it would have been better, instead of offering fast food Pizza and a fizzy drink.