I don't know much about Hackensack, but if your wife is Japanese, Fort Lee and Edgewater are definitely good choices. I believe there are many ex-pat Japanese families living in both towns and both towns also seem to fit your overall criteria. The NJ transit bus lines are pretty ubiquitous in both towns, as far as getting around or into NYC.
One big plus that Edgewater might have is the Mitsuwa Marketplace, which is basically a Japanese strip mall, with the Mitsuwa supermarket as its centerpiece store. The supermarket is what you'd think of as a regular supermarket, but also with various mini-stores like a travel agency and food court. Many signs are in Japanese only, but most things are also labeled in English. Other stores in the strip mall include a Japanese bookstore and a Japanese restaurant right on the Hudson river and. There are other stores, too, but I can't remember what they are off the top of my head.
Ah, actually found a website with some pictures of Mitsuwa:
http://offthebroiler.wordpress.com/2...a-marketplace/