Thinking of Moving to Linden, New Jersey

I don't really know Jersey that well, but being formerly from NYC (Park Slope, Battery Park, Astoria and, yes, Flushing too) I would say one thing you might want to consider is making sure you're in an area that is walkable - maybe something that is kind of like a village where you have close access to the main drag. If you get too way out in the burbs, where you can't get anywhere without driving, you might find it very isolating. Where I live right now out on the Island, going into town or visiting friends is always a bit of a schlepp. Fortunately I live a close walk to the beach and that more than makes up for it. Make sure you find something close by that you really like in whatever community you choose to live in.

Personally, I would never move to NJ because of their outrageous property taxes but perhaps living in NY your whole life you are used to high taxes?

I live outside of Philadelphia and our taxes are high enough IMHO.

Good way to ruin a frienship. Right next door?
do not base friendliness of neighborhood on one visit. You have a lot to consider yiu do not drive,car, commuting Think ling and hard about a change like this one

Have you considered Queens neighborhoods that have a more "suburban" feel, like some parts of Forest Hills? NJ has lots of beautiful towns that are an easy commute from Manhattan, but if you like Queens there are certainly great neighborhoods in Queens too! (I personally am happy in Brooklyn.)

ETA: You're correct about needing a car, that's really true of most parts of NJ. Another benefit of Queens!