Off the top of my head, Maryann's Mexican Restaurant at 1503 Second Avenue. There are other locations, but I have never been to them. The margaritas and the food are good and reasonably priced.
Dallas BBQ is also fun and reasonably priced with locations around Manhattan. Here is a
link to their website. I never had alcoholic drinks there.
If you are looking for other fun and moderately priced restaurants in NYC, I suggest you check out
citysearch. Good luck!