Hi Thomagr,
Data from a few years' ago...
I lived on the UWS and the easiest for me was HPN White Plains Westchester County. It's an easy drive up the Parkways, it doesn't take too long and the traffic's rarely bad. When I lived there a few years ago, there were two schools renting aircraft - one was all Cirrus, the other mainly Cessna. When I needed a checkride or something, I used the guys at Performance Flight (the Cirrus place) and they were always great. A quick web search should turn up what's available now. HPN's also really convenient for doing Hudson River flights and day trips out to MTP Montauk and the islands. I was really happy being based there.
I used to have my aircraft serviced at Farmingdale. That was always a slog getting out of Manhattan and then the LIE is just the most horrible drive. It's always busy. However, if that's more convenient for you, there may be more choice to rent from. Unfortunately Ventura, who were great, have closed their flying school, so I imagine they've now sold off their rental fleet.
Linden is probably the closest to you as the crow flies. I went there once. It wasn't a particularly quick or convenient drive and the airport struck me as pretty bleak and unattractive.
If I couldn't have been based at HPN, I probably would have picked CDW Caldwell Essex as a second choice. Again - nice airport and not too hard to get to.
Once you've narrowed it down to 2 or 3 choices, it's worth getting a ZipCar for a day and driving out to take a look. You can only really judge how good somewhere is to rent from when you've taken a look round and met the people.
Good luck!
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