there's an italian place on the South End, totally forget the name of it, but there's one on Newbury that's always a 2 hour wait, and this is the same place, same owners, menu, etc. and never crowded, great place to be romantic - anyone know what I'm talking about?
if all else fails, take her to Denny's, tell her she can get anything she wants on the menu except the Lobster, order a Grand Slam for yourself so you have plenty of jokes to make, I think you'll be in good shape
(good luck!)