Is this just the two of you? If so........California Grill is a good start. Le Cellier, Chefs De France......maybe shulas at the Dolphin.......if there are other people of different ages going......then Crystal Palace is excellent, and Chef Mickeys too....
If you want it to be very very special, go to Victoria & Alberts. If you still want it to be special and not spend quite as much (but it's still pretty expensive) try Bistro de Paris. If you want something on the DDP, try JIKO. These are the only three WDW places that will probably offer a more quiet, romantic, adult atmosphere. I love CA Grill too, but it's noisy there. So is Narcoosie's, Brown Derby and it was pretty noisy last time at Artist Pointe although many people find it to be a romantic setting. Yachtsman Steakhouse is pretty nice too but I wouldn't consider it romantic there. We are trying bluezoo this time but can't tell you anything on that one yet!!!
We haved dined at Yachtsman Steak House on 3 out of our last 4 anniversaries. We always had an amazing meal there. We have gotten free dessert each time, a rose once, and personalized menus once.
I vote for Artist's Point-my DH still talks about their berry cobbler-we had our 5th anniversary dinner there! I have done California Grill also;just find out what time wishes is so you can pick your time accordingly!