when there i stayed at this hostel in harlem for a few days called jazz on lenox. it was cool and cheap. i wish i would of stayed there longer. lots of black people there if those types scare you though.
brooklyn was my favorite place to party. no bar in particular but i think it was broadway st. that we were on. it seemed like a "hip" place with fun people...at least 2 years ago it was
also union square park on weekend nights was a lot of fun. freestyle ciphers, break dancing ciphers, soccer juggling circles, talentless musicians, drugs, alcohol....lots of fun to pre party at with your own booze and smoke before heading into a bar. and watching people rap battle along with their crews representing their boroughs and actually yelling shit like "where brooklyn at!!!"
as for food lots of good places but i personally just loved the street carts and trucks that sold gyros and kabobs. those were the shit!!!
i went through harlem, the bronx, brooklyn, day time, late at night. at no point felt threatened. maybe i was just lucky though. the cops were even pretty cool too (at least in manhattan). youll have a great time. after new orleans, id say ny's been my favorite city in the u.s. that says a lot considering i live in the greatest city in the world, san diego. after tomorrow i dont think new orleans will exist anymore though