There are three great Chinatown areas in New York: Bensonhurst, Flushing, and Lower Manhattan. The last one is mine. I've been going there for years and it's barely changed. If we are lucky we never will.
Like the restaurant to which it is most often compared, Ping's, this is a very high class Chinese banquet restaurant specializing in extremely fresh seafood. As in, the fishes are swimming around in aquariums and are bumped off when you order them. If all you got was seafood at Fuleen, though, you would be missing out: the biggest difference between it and it's rival is the presence of fabulous meat dishes, such as soy sauce baby chicken and a fine version of Peking duck.
Some of the best jerky you'll ever eat comes from this obscure Chinatown storefront. It's not grossly chewy and smoky, but rather more like a fruit roll-up. The biggest reason for its excellence, I think, can be found in the fact that pork jerkies, rather than beef, are the name of the game here. Cured pork just tastes better than beef, as anyone who ever ate bacon will tell you.
You can have three guesses what you should order at Peking Duck House, and here's a hint: it's not egg foo yung. A specialist in one (very difficult) dish, this is the place to go for laquered, slow-roasted pekin ducks, ceremonially sliced and served on a large platter, and accompanied by soft crepes, plum sauce, and scallions. Don't bother asking for a menu.
Chinatown offers some of the most authentic regional food to be found in America. But you won't find it at Wo Hop, possibly the greatest remaining bastion of old-school, Cantonese-American working class food left in New York. Here still may be found the chow mein, lobster cantonese, spare ribs, and egg foo yung which defined Chinese food to four generations of New Yorkers. You can make that a fifth, as the young people still drink and get an urge late at night for the Chinese food of childhoods.
Famous as a late-night chef hang because of its late hours, the fact is that the best thing here, the crunchy pork, is really only good for the early part of the day. Many late night visitors underestimate the place as a result. Of course, the Cantonese menu, consisting of things that don't hang in the window, is also well worth a trip.
Widely considered the best Shanghai-style restaurant in New York, Shang Hai Cuisine crosses the finish line against a strong field: just on the same block can be found stalwarts Nice Green Bo, Joe's Shanghai, and 456 Shanghai within a few hundred feet. All have their strengths, but a Shanghai restaurant is judged by its siu lim bao (juicy buns) and the ones at Shang Hai Cuisine rock: the dough is thin and the meat coarse, the broth both unctuous and flavorful. Run don't walk.
It's a touchstone for cheap-eats mavens because of its outrageously cheap (and outrageously good) stuffed buns, but the real attraction here ought to be the char siu (Cantonese roast pork) which is the best in Chinatown by far. Look out, too, for the rare "flattened duck," which looks exactly like it sounds; although the regular Cantonese roast duck is excellent, this version, semi-cured and concentrated, brings it to another level.
The eternal debate lingers: Wo Hop or Hop Kee? The two restaurants are in fact almost indistinguishable, and to make matters even more confusing, they are right next to each other on Mott Street. If pressed, I would say that Wo Hop does the classic Cantonese-American dishes better, and Hop Kee the (slightly) newer dishes, like spicy salt pork chops, or black bean crabs. Neither restaurant can really be said to cater to Chinese customers, but there is a legendary Chinese menu unavailable to English speakers. Bring a translator!
This is gourmet Chinese banquet food at its best, or at least the best you're likely to find in Manhattan. (Ping has an even better restaurant in Queens.) A rare chef-driven Chinatown restaurant, Ping's serves very fresh, very exotic, and very expensive dishes to discerning customers. Winter melon, fresh abalone, seafood stuffed shrimp, flounder two ways: you can find a lot to love at Ping's. Don't bother with the dim sum. It's good but no better than many other places, and the seafood here is nonpareil.
A relatively recent addition to Manhattan's Chinatown, XO represents the current state of Hong Kong cooking, as opposed to the antiquated and Americanized Cantonese food to be found at the Wo Hops and Hop Kees of the world. The size and range of the menu is astounding, and only a large, hungry group can hope to even get a sampling of its riches. Not all modern Hong Kong food is great, but it's all different, and some dishes, like squab or baked giant shrimp over rice, will make you thing twice about going back to the old ways.