Hi David!
Three places come to mind: Victoria & Albert's, Bistro de Paris, and the California Grill.
Victoria & Albert's in the Grand Floridian is probably the ultimate dining experience at the Walt Disney World Resort. The restaurant does not all young guests and has won the prestigious AAA Five Diamond Award. It's expensive, but you will be there about 3 hours. Everybody I've talked to who has dined there has said that it was worth every penny. You can get more information on Victoria & Albert's
here.
Bistro de Paris is easily the most romantic restaurant in any of the theme parks. It is located in the France Pavilion in the World Showcase portion of Epcot. The service and food is incredible; unless you are sitting by a window, you will think you have been magically transported to Paris! It's only open for dinner and you'll find it above the more familiar Chefs de France restaurant.
The California Grill is located at the top of the Contemporary Resort. It has good food, great service, and an incredible view of Walt Disney World! Plan you dinner at the right time and you can watch the Magic Kingdom fireworks Wishes from your table. Or you can go outside on their private balcony to watch the fireworks from a unique vantage point. If you eat earlier in the night, you can leave the restaurant and return for the fireworks just by showing your receipt. You can get more information on this fabulous restaurant
here.
Enjoy planning!