Passaic is a very heavy BT community that people consider "out-of-town" but isn't really so much (though, to give it credit, there are a decent number of people from out of town living there). It is a very warm community and the suburban-style setting and park in the middle are really nice.
There are a LOT of shuls in Passaic. I've only been to a few of them. My favorite is Ahavas Yisrael, which is located right in the middle of Passaic. Most of the shuls are pretty right-wing yeshivish, with the possible exception of the Young Israel and
the Adas, but in general, the community leans to the right. It is very heavily influenced by the BT yeshivas and seminaries in Israel (especially amongst the singles, but with the marrieds also), and recently, I was at large meal where I was the only person present who had not spent a significant amount of time in Israel at a BT institution.
There are two main schools in Passaic, with a 3rd having just completed its first year. The Yeshiva Ktana is very right-wing and the largest school in Passaic. The Hillel is slightly more to the left, but that doesn't really mean "modern." Classes are still all separate gender. And the Clifton Cheder opened this past year and uses some Montessori-ish techniques but is still pretty right-wing.
There is one bookstore in Passaic - Z Berman's. It offers a decent selection of seforim and Jewish books. There is also a gift shop that sells books also (not sure of the name of the store, but it is on Passaic's Main Avenue.
There is one exclusively kosher grocery store, Kosher Konnection, located on Main Avenue. Until recently, it did not offer produce, but is currently in the middle of an expansion that will allow it to offer produce in addition to other groceries.
There are also a few other stores on Main Avenue - a robe store, a clothing store for women, a clothing store for men (I think).
There is one bakery, Yoichie's, on Main Avenue. It's yum and sells pretty much everything you need. The exceptional thing about Yoichie's is that they offer all new residents to Passaic a free cake. What is so exceptional about this is that Yoichie actually recognizes if a person is new and offers them the cake.
There are a few restaurants, all but one located on Main Avenue. There is Jerusalem Grill, which offers Israeli food, Jerusalem Pizza (which is pizza), Win Wah Chinese Food, The Main Ingredient, which is homestyle stuff, Bagel Munch, and Izzy's Pizza. (It's possible I missed one, but I think I got them all.) They are pretty self-explanatory.
I don't know anything about the youth groups, if they exist in Passaic. Passaic does have a pretty active, although somewhat older, singles community.
Contrary to the popular opinion, Passaic is NOT far away. It takes about fifteen minutes to get Manhattan, which actually makes it closer for many than Brooklyn.
If you have any questions, Luach is a good place to look.