So it's my birthday this weekend, and three of us (hip women in our late 30s) are going to the ballet at City Center on Saturday. Any suggestions for a nice place for lunch around 55th and 6th Ave beforehand? I'm usually a downtown & Brooklyn 'hound, so don't know much about Midtown. Looking for nice atmosphere, not just a burger place but not wildly stuffy/expensive either. French, Italian, American...really anything tasty. Thanks!