This might be a little obvious, but when my wife and I get away alone, I've found that the most romantic spot is the hotel room.
Married people, you know what I'm talking about! There is nothing like a hotel room to get the fires burning again, am I right? Who's with me on this??
On the other hand, if you are looking for a place that is romantic in a quiet, peaceful way, my recommendation is the hotel room immediately before and after bomp-chicka-wow-wow.
Do you mean inside Disneyland Park? Can't help you there, that place is pretty much a zoo.