Superfoody visiting NYC and Queens/Bklyn
You may want to post specific questions on the Outerboroughs Board; you'd probably get more replies.
That said, I like this thread a lot and have referred back to it when DH and I are heading to Queens. You have to scroll through all the replies to see how the list grew and grew ... http://www.chowhound.com/topics/367338 .
As far as a good mix - Sunset park in Brooklyn is very good. Try Tacos Matamoros on 5th ave and 45th street (buy yourself a beer to bring in) and get yourself some Al Pastor Tacos. Also Ba Xugen on 8th ave and Lucky 8 on Eight too. Try all the pizza you see in BK that isn't a chain.
I'd recommend the 63rd Drive subway stop in Rego Park (Queens). Within a quarter-mile radius you'll find great pastrami (Ben's Best---NOT the chain), REAL NY bagels (Bagelette), AWESOME Indo-Chinese (Tangra Wok), delicious Turkish (Istanbul), several Russian and/or Polish delis and markets, a Middle Eastern market, an excellent Asian market (Jumbo), and a Uzbeki restaurant (Cheburechnaya), which gets rave reviews here, but I've not yet tried. There is also Sushi 33 which has the best shu mai I've ever tasted.