From Miami Airport to Key Largo - Dinner
take the dolphin x-way (836 west)to 87th ave and head north. there you will find a plethora of chain restaurants you are sure to recognize. Flanigans is a small local chain which has excellent ribs and dirty rice, they also do a nice prime rib, great burgers, fish sandwiches and salads...good wings too! another option would be Shorty's BBQ which is another smaller FLA chain. Good BBQ. Then there are the rest of the chain joints you might find in any town in america, Hooters, Longhorns, Chilis, etc. I'm trying to keep you close to the x-way whilst on the way to your final desitnation. Once down in Key Largo try Calypso.
From MIA to Key Largo, you're probably going to take the Florida Turnpike until it runs into US-1 around Florida City, then continue South to Key Largo. There won't be much b/w Florida City and Key Largo, so you'll want to find something before FC.
For a great neighborhood restaurant, I'd actually recommend heading just a bit north of the airport on the Turnpike to SW 41st Street, an area we call Doral. It's not far and you'll be headed against traffic if you're landing b/w 4-7, though in Miami-Dade County you can hit traffic on an interstate anytime, anywhere. Then when you're done with dinner, traffic heading south will be better and you can drive south comfortably.
But back to your question...go to SW 41st and head East to a great local place named Peruvian Seafood Restaurant. The name should tell you what their specialty is, though they have a broad menu of delicious Peruvian food. And you MUST have their lemonade -- one of the best in SoFla. Also in the same plaza is Mrs. Mendoza's, a local Mexican take-out favorite with limited seating and delicious Tex-Mex.