Hey I am only 26 and I had some classy 19-23 year olds and quite frankly there is so much B&T money those kids can probobly afford better places than I go to now...there are a TON of restaurant s to pick from...if you want to be with similar age go to menupages.com and pick any place with a good rating on the lower east side, chelsea, or if you are down for it, go to to Brooklyn!
IMO the BEST meal for a b'day is a steak but that is $$$$$$$$$$$$$$ in NYC
My friend had his b'day at Mama Mexico in the high 40's on the East side...food is decently priced but watch the booze...thats where they make their money....seriously though, the BEST...if you are a group of depraved males like me and have more than 10 people go to Churrascaria Plataforma, their is one in midtown 48th and one in Tribeca, for $70-$80 pp it is UNLIMITED BRAZILIAN BBQ and BOOZE. Unbelieveable! Pricey for young folk but the + side is that you won't need to (or be able to eat) for several days afterwards.