Avvio in Garden City is quite good. Just make sure you make reservations.
I've enjoyed the food at the Greenwood Inn for over 20 years. Reasonably priced snd friendly atmosphere. http://www.greenwoodinnri.com/
Greg's is quite close and very popular for casual dining.
I'm not familiar enough with the area to say. We ate at the Iron Works Tavern which was good and is about a mile from the theater.
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