I agree with others, try a big lunch instead of dinner.
Also, consider sharing your entree. Disney is great about that and no one ever bats an eyelash. DH and I usually order an appetizer and share an entree. We always have plenty to eat and sometimes can even find room for dessert. I don't like leaving a restaurant overly stuffed!
Here are some of my reviews for DH and I on our last trip -
Sit Down Restaurants
ESPN Zone - Boardwalk - While the ESPN Zone wasnt our first choice we decided to eat here so we could watch what turned out to be an incredibly horrible football game. We didnt arrive as early as we would have liked so we had to stand in line, but the line moved fairly quickly. DH had the hot roast beef sandwich and I had the grilled chicken sandwich with swiss cheese. Our food was standard sports bar fare, but we have no complaints. I had a mudslide and DH had a couple of beers in the process of watching the game. Later in the evening we also shared the apple brown betty with ice cream (an extra $1 for the ice cream). It came out nice and warm and was very good. We will return to ESPN if we want to watch a game, but I think we would eat someplace else on the Boardwalk if there wasnt a game. If you dont count drinks our meal with entrees and dessert was around $23.00
Brown Derby / MGM - We had a PS reservation for lunch at 1:00 at the Brown Derby. We were ready to eat a bit early though and really needed a break. We walked into the restaurant around 10:45 or so and asked them if we could change our PS. The said just to come back at lunch time and they would get us seated. We returned at 11:30 and put our names down for lunch. I think we waited about 10 minutes. We loved the interior of this restaurant. It was our first time and we both thought it was really fun. I started out with portobello mushroom, Laura Chenel's chèvre cheese ravioli with tomato-fennel sauce and basil and DH had a cup of tortilla soup. Both were very good (we share well)! We then shared the Grilled 10 oz. NY Strip Steak marinated in Ale with chimichurri and boniato mashed potatoes. Our waiter was nice enough to let them know that we were sharing our entree and it came out already split in half for us. Neither one of us had any problems finishing our halves, it was soooo good! The flavor on the steak was wonderful! We had to finish off with a piece of grapefruit cake since I had heard how amazing it was. I think because the cake was so hyped up, it disappointed me a little. We both liked it and dont get me wrong, we finished it, but neither one of us thought it was fantastic. We left very happy and very full! Total for lunch with DHs beer was $44.00
Coral Reef / Epcot - We ate here on our honeymoon 4 1/2 years ago and decided we were long overdue for a return trip. Both of us were craving the lobster bisque so thats what we started out with. I dont even want to know the nutritional information on this soup, on vacation, all rules are out the window. We then shared a grilled mahi mahi on a bed of garlic mashed potatoes. The potatoes were full of garlic and very good. The fish was a little bland, without the potatoes it would have been too bland and needed some seasoning. We passed on dessert today. Still one of our favorite restaurants we will definitely be back to watch the fish and enjoy a great lunch. Total for lunch with no beverages was $31.00
Spoodles / Boardwalk - We have only eaten breakfast and Spoodles and we enjoyed that so much that we decided to try dinner. We walked through Epcot and made our way to Spoodles for a 5:00 PS. We started out with the roasted garlic and four cheese flatbread - it was sooo good! I dont know exactly what kind of cheeses are on that, but its a great combination. We also added chicken to the flatbread. DH had a soup of the day, but I dont recall exactly what it was. It was a tomato base with sausage and vegetables. Whatever it was, was very good. We then split the Orecchiette Pasta - "Little ear" shaped pasta with chicken, spinach, pepperoncini peppers, olives, tomatoes and peas tossed in a light chicken broth with feta cheese. We added shrimp to it as well for an additional cost. DH liked this more than I did. He rated the soup and flatbread higher, but still thought it was good. I didnt eat a lot of mine. It was a little spicy and I didnt care for the taste of the chicken. We will definitely be returning to Spoodles for dinner again, well just try something different. Our total for dinner with 2 glasses of wine and no dessert was $52.00
Plaza Restaurant / Magic Kingdom - We just shared a club sandwich minus the mayonnaise and that was it. We passed on ice cream and decided to stop in candy store on our way out instead. The club sandwich is good although it could have used a slice of cheese. We love the plaza because its a nice place to sit down and you dont have to make a PS for it, so its flexible. Our total for just our club sandwich was $11.00
Beaches and Cream / Beach Club - This was a last minute addition to our plans. We were wiped out from our day in the park and needed an evening off. I told DH the plans were up to him. His perfect evening in WDW? Beaches and Cream followed by mini golfing! We walked right into Beaches and Cream around 5:15. We each had hamburgers, DH a cheeseburger actually and we shared a malt. Burgers, fries and ice cream were delicious as always! We never dislike a meal at Beaches and Cream. Total for dinner and malt (just water to drink) was $20.00