What is  the best thing to order  in a fish restaurant? ?

Only thing I would order is Fish and Chips........Cod. 

I am deathly allergic to all shellfish and squid, and you wouldn't catch me dead in a seafood restaurant.......(or maybe you would, if I entered one) ......because even something cooked in the same pan or oil could kill me. 

The smell alone sets me off. 

But I did  like Arthur Treachers Fish and chips when it was around,  because that's all they served.....so it was safe enough. 

 steamed river trout

Cod is good, shrimp is also very good.  Salmon is good as well.

Well Australia has the best    Fish in the world the build dams  won’t kill fish the government  engineers  in upper Queensland  can build cities  there to bring goodness    

That depends on what's on the menu. I'd prefer lobster if they have it or whatever the fresh catch of the day is.

swordfish                  

fish                                            

Seared ahi or yellowfin tuna. Red in the center, if you would eat a steak rare, pink in the center if you prefer medium rare. I actually like it *better* than steak. (And it costs more per pound.)

Swordfish is a similar meaty fish. People who say they don't like fish generally like both ahi and sword. Given a choice, I prefer sword grilled rather than seared or baked.

Salmon is always a good choice if you're not feeling quite that adventurous. A restaurant devoted to fish probably has wild-caught and prepares it in interesting ways.