Petit Robert Bistro - Reasonably priced and sophisticated french cuisine, you'll definitely impress your date with this place without hurting your wallet.
Coppa - Trendy, hip and no reservations needed. Plus you can stop by the franklin cafe after to have some drinks if you decide she's worth keeping around...
Teatro - I used to go here for my first dates, the food is excellent and the place is near all the clubs as well as the movie theater. So you get to decide depending on how the girl turns out, if you wanna have a wild night you can go out and if you wanna lay back you can go to the movies.
I love Trattoria Toscana. Its romantic, the food is fantastic, waitstaff impeccable.
Go to The Hungry I Restaurant | French Cuisine for dinner and then take a stroll through Boston Commons! Great food, really romantic.
Island Creek Oyster Bar--order Snug Harbors. Delicious. Or Drink!!! Another great spot.