My date and I went to Arno Ristorante for a Friday 6PM dinner just before heading over the the Nederlander Theatre on W41st (easy walking distance) to see Rent at 8PM for $20 a ticket (they have a 5:30 lottery). Bottom line: total $155.00 dinner for two with one $45 bottle of wine, shared dessert (either very romantic or very cheap, not on the table for the first date), and a very entertaining Croatian waiter who was attentive but not overly so. The host and his captains were very solicitous on the way in, took our coats personally. We sat toward the front, away from the door, at a table for two across from the mirrors, which was great because you get two angles on your date. The ambient sound level was comfortable, you can have a private conversation easily without raising your voice over the table. There were some family groups (actually a good family destination), but they were all unobtrusive. You could easily go to $300 with a more memorable bottle of wine. The lighting was just right for gazing into eyes without being distracted by too much detail. So much for the ambiance, it's very good.
As for the food, the first thing you should know is I believe that Arno Ristorante uses real virgin olive oil, as opposed to a common substitute, because the Insalata Di Cesare was really exceptional, as well as Broccoli florets, which we specifically ordered sauteed in virgin olive oil and garlic. As for my main course, Rigatoni Amatriciana, I've had better at Papa Razzi (the one in Cambridge, MA). My date had Pollo Castelli, but she didn't rave about it. We were also pleasantly surprised by the desserts, which came over on a large cart and are sliced it at the table, which I thought was a nice touch.
On my romantic scale (0-12) it's a solid 8. You won't slug a home run, but you won't strike out either. The bar is really impressive if you have to wait (we didn't). Easy walking distance to all the Times Square theatres, as well as to Penn Station.