Robin, your question is very broad, of course. As I know my own nabe best, I'll say most about that: The two most interesting strips of restaurants around me are:
1. along Atlantic Ave between Court St and Henry St -- many are Middle Eastern but there is also a "chippie", a serious ale house, a thin-crust pizza place, and a Spanish restaurant
2. along Smith St between Atlantic Ave and Union St (and even beyond) -- this is the restaurant row, so I can quickly think of places for vegan, French (several), Japanese (several), Peruvian (down from 3 to 1), Italian (several), Thai (several), Indian, Dominican, Vietnamese; there are also several excellent cocktail places, if it's going to be that kind of lunch...
To get to #1, take the 2/3/4/5 train to Borough Hall and walk. To get to #2, you could do the same or take the F/G train to Bergen Street.
Area map:
http://tinyurl.com/3qgt5uhW/r/t Dale's suggestion of Grimaldi's: that is down by the base of the Brooklyn Bridge, where there is a lovely new park, so it might be worthwhile.
[ Is this the kind of help you're seeking, or would you rather that I try to name a specific place? If your friends have preferences, that helps. ]