I don't know the area very well but from what I've seen you'd do better to head away from NYC than towards it, from Woodstock, it all seemed to get a bit grimy the nearer the city you got. Adirondack Park looks like a good bet especially if it's anything like Vermont which isn't too far away either if you don't mind a bit of driving.
we have a day spare in the US leaving Woodstock and ending up in NYC 2 days later . will be travelling by car and wonder if any one has any suggestions of places that would be nice to visit to pass this day . we would prefer non city as this is a couple of days sandwiched between a stay in boston and a stay in NYC so ideally coutryside / lake/ mountain etc . I dont kinow this part of the US at all so any tips gratefully recieved. will be there next week