If you like live music and a pleasant Caribbean atmosphere, try the Bahama Breeze restaurant on Int'l Drive. Nice bar and good food at a reasonable price.
If you don't mind a little further drive, visit Loews Portofino Bay Resort Hotel next to Universal's parks. There are several restaurants, some more couple-oriented than others but strolling along the water's edge, with live Italian music wafting past from the restaurants... the European setting, the beautiful waterside lighting, it's all very romantic. You can take a free ride on the boat back to CityWalk or stroll the long, lit walkpaths to the other resorts. CityWalk has Parking at the Universal garage is free after 6:00 pm.
If you want to make a day of it, drive out to the Gulf Coast, to the Clearwater area, ~1.5 hrs. After shopping, boating or enjoying the beach, have a seafood dinner at a restaurant overlooking the ocean, with a sunset view. For us, that's romantic!!!
If you like the boat on the water idea but you want to stay nearby, choose a restaurant in Downtown Disney and end the evening with a water taxi ride on the lake there (free) or ride the water shuttle up to one of the Disney resorts for a walking visit. This is not offsite but it is nice. I also think the waterfront restaurant at the Grand Floridian is
so pretty but we haven't eaten there so I can't comment. The area around Crescent Lake behind Epcot is beautiful at night too, a bit more romantic in the Yacht Club area (to me) than near the evening bustle on the BoardWalk. So a nice restaurant at Swan/Dolphin or one of the Disneys in that area is a good choice too. It's been quite a while since we've eaten at the nicer sitdown restaurants there so you may want to look in the Restaurants forum if you want specific recommendations on Disney restaurants. HTH with ideas.
