Sure, there are Pearl Oyster Bar and Marie's for affordable good seafood. Then there are Aqua and Le Bernardin, for good seafood without the 2 hour wait (BUT prices are stratospheric). How about a restaurant where you don't have to wait AND the food is incredible?
Mario's - in the West 20s (between Madison and 5th Avenue).
The food: Fantastic seafood, from the basic mussels in white wine sauce (the best mussels I have ever had, outside of my Sicilian raised mother-in-law), to perfectly prepared red snapper to the tender, sweet lobster. I wouldn't be surprised if Mario cast out a line and brought the fish home himself!
The atmosphere: Simply, the atmosphere is almost non-existent, or so many would think. The 1 room atmosphere reminds me much more of a Brooklyn diner in the 1960s than a Manhattan restaurant in the 2000s - a place that you could almost see the cast of Goodfellas hanging out at. For me, it was actually kind of charming. The back of the restaurant has an old oak bar, where Mario can be seen having a drink while he looks out over the restaurant.
The service: Among the best I have experienced since living in Manhattan. The friendly Irish waitress struck up a great conversation, and made me feel like part of the family. This was a type of service that just doesn't exist anymore!
I am in no way affiliated with Marios, but I just wanted to share the positive experience I had there. Go for the food and go for the service, but don't necessarily go for the wine or atmosphere. This place works great for two chowhounds, but not for a first date.