Coronado Springs Resorts - Tower stay is really nice for a couple, you can walk and do a tequila tasting across the bridge if you want and plan.
I like the EPCOT area - Swan.
We've also stayed at Art of Animation - enjoying the skyline and the Petals bar at Pop Century with our favorite bartender, Gordo (now bartending in Hollywood Studios, highly recommended!)
We've recently stayed at the Conrad Orlando, which is not on Disney property, but an actual full resort onto itself. It shares a "beach" that is ultra blue with the Evermore resort and quite luxurious, tho I'd not recommend going to Disney as the price to stay there is quite high, and there's so much to do at the Conrad, such as renting boats, rope swings over the water, etc. Food is limited at the Conrad - but the Evermore had many restaurants to choose from - with less stuffy prices.
If going to the parks is more your thing, I would recommend the EPCOT area resorts, with my favorite being the Swan and Dolphin, which includes the Swan Reserve.
They have mini golf options at the Fantasia Gardens, which is a lovely romantic competitive sport, and then you can walk to Beaches and Cream to pick up some ice cream at the window while you wait the fireworks at EPCOT.
Can you just imagine taking a romantic walk here?
The mini golf is fun, I do not recommend doing the putting greens as it's more serious and focus on the golfing aspect rather than the fun nature of an afternoon out with your sweetie.
This is a kids scoop of cookies and cream ice cream, with a cherry on top
Or a more robust cookie sandwich with cookies and cream stuffed in the middle. Can you guess what my favorite flavor of ice cream is?
I hope this helps, and I would love to hear others comment on romantic resorts to stay at Disney World, as I think ALL of the resorts are great, and you just need to know what you want and your goals for the trip.