Steakhouse 71 if you want a steak. The quality is pretty good considering you get a steak and a side for under $40.
Sebastian's Bistro offers sodas, rolls, salad, a 4 entree platter with sides, and dessert for $39 per person.
Wine Bar George's lunch and brunch menu are great, and the portions are big for the prices. Dinner is very good too, but the menu is mostly small plates with a few more expensive entrees.
In the parks, Diamond Horseshoe for $45 per person and Biergarten for $49 per person are decent deals. 50's Prime Time offers good value for their plate sizes, but the food isn't my favorite. Jungle Skipper Canteen is the one non-signature, table service restaurant I make a point to go to in the parks.