Casual in the theater district
There are literally hundreds of restaurants in the Theater District. So, you need to help us narrow things down by giving a few specifics.
1. What cuisines do you prefer?
2. What is your budget for lunch? For dinner? And tell us if the figures you give include drinks, tax & tip.
For lunch, I'd say we are looking for something very simple, sandwiches/salad/pasta/veggie options, no drinks maybe even self-serve.
For dinner, anything Asian or Mediterranean or even American fare. Hell's Kitchen and Vynl seem like good recommendations for dinner. Not looking to spend too much time at dinner, nor too much money (We are seeing 2 dramas on Broadway after all). Drinks not an issue.
For lunch, Uncle Nick's would be my suggestion. You can see the lunch menu on menupages.
As for dinner, here are a few good possibilities:
Enjoy the shows and Bon Appetit!