California Grill - They gave us a really good window table and decorated it for us on our honeymoon. A guy also came and took our picture and then e-mailed it to us a week later. It can be loud in here, especially if it's getting towards fireworks time, but the view is sooo worth it. Then you can go out and watch the fireworks from the observation deck together!
Victoria and Alberts, Narcossees's or Citricos - The Grand Floridian is very romantic feeling to me so I would suggest eating at one of the restaurants there. If your budget can swing it, definitely do V&A. It's so romantic and is an amazing experience. However, you can't go wrong with either Narcossees's or Citricos!
Any of the other signatures would make for a good honeymoon meal as well!