Two "combo" suggestions for a memorable anniversary:
First, Dinner at Artist's Point in Wilderness Lodge ~ have dined there twice and I believe it is one of the most intimate/smallest restaurants at WDW. Followed by a boat trip to Magic Kingdom, and a sit down Chocolate Dessert with a balcony view sit-down view of the Fireworks Celebration. (Spoiler Alert: near the end of the show, Tinkerbell lands on the roof, by guy-wire, right above your head ... and She is a He!!!)
Second, Epcot has great dining for every taste. Le Cellier Steakhouse in Canada, Tuto Italia at Italy, in France go to the Chefs de France. Or, just around the corner at Flying Fish on the Boardwalk. THAN finish the night with the New Harmonious Fireworks cruise on the Epcot Lake. WARNING: You miust be Wicked Organied to get rhat reservation ... do your research!
And BIGW/OS because it goes without saying, I Will Say It: Look at the menus in advance and find a place with selections that spark both your taste buds. Happy Anniversary.