I haven't been in years, but G&M, a family restaurant has good native food (sour beef and dumplings) and is known for its giant crab cake. The crab cake isn't Maryland style, but many people like it (and some hate it ). A little farther west on MD100 is Timbuktu - another local family restaurant. Not fancy but comfortable and tasty.
In Arundel Mills, one exit west of BWI on MD100, there are lots of restaurants. I think the Indian food at Rangoli is very good. I've stopped a few times to recharge my car in the garage there and have had very good dinners and friendly service.
If you are going all the way to Timbuktu from the airport, just go to Gunnings and have good excellent crabcake instead.
What do you mean the G & M crabcake isn't MD style? I used to go either there or Gunnings when we lived in MD and got the broiled crabcake and they were similar. I don't know barely any MDers who do the "fried" version if that is what you mean.