Will have 1 week free time at the end of February, will be around NY. Would appreciate your advises on where to travel by car (scenic roads, parks, attractions, sightseeing) in DC, MD, NY, PA, MA? I am from Russia, not living in US. Thanks!

February is not really the time to look at the countryside. No leaves, no flowers and everything looking brown and crunchy - if not covered with snow or ice.

If there are specific sights that you want to see (tell us your interests and we can give info) but unless you're into skiing - or looking at melting snow and ice there's not a lot to do in Feb. And lots of places are either closed or open for only short hours due to lack of tourists. Really you would be better off in the cities.

Are you interested in American historial sights (civil war battlefields, president's houses, revolutionary war villages)? Cute small towns? Antiquing?

Although much of the countryside is beautiful in spring, summer and fall - in the winter it's mostly just blah - and once off the major highways driving can be a real pain in the butt.

I agree with nytraveler that, at that time of year, you might be better off in the cities. Without knowing any more specifics about what you're interested in, I would suggest heading to DC for three or four days, and then stopping in either Baltimore or Philadelphia on your way back to New York. Will you have already had any time for sight-seeing in New York City itself? If not, I would probably save a couple of days for that and just pick one other city, that is, DC or Philadelphia.

I would agree that a visit to Washington, DC with a stop in Philadelphia would be a good idea for February. You would not need a car. This type of trip could easily be done on the train.
Or, you could take a ski trip to Vermont or New Hampshire but this would be dependant on the weather. It could be a big success or a big disappointment.

I'll also agree Feb. is not great for scenic outdoors unless you want to go skiing. I also agree you should dump the car, concentrate on the cities and use train or bus (very cheap). Even without the price of the car rental, with the price of gas/petrol and parking costs in the cities, public transportation will be cheaper. Philadelphia is even an easy daytrip from NYC by train or bus.

If you do decide to drive anyway, I'd head to DC and maybe stop at the Winterthur estate on the way. http://www.winterthur.org/about/about.asp

Well, I don't think its such a bad idea, if this is your only chance to see the area. It is obviously not the best time of year, but you could take a meandering drive with a couple overnights, then end up in DC for the remaining time.

Something like this might work (get out your map):

Head west from NYC and then drive south along the Delaware Water Gap. This is a national park on the PA/NJ border. The visitors center is closed, but the roads and views are not. The park center web page has some suggested driving routes.

The region between Harrisburg and Philadelphia is rolling farmland, with a large Amish population. The Amish are a group originally from Germany, that do not believe in using modern technology -- they dress in black, drive horse&carriages instead of cars they are famous for some types of crafts.) Two interesting small towns in this region are Hershey (home of America's biggest chocolate company, the whole town smells of chocolate, and they have a nice visitor's center), and Lancaster (a center for Amish culture -- you can eat great meals and maybe tour a farm).

(Harrisburg is an industrial city with not much attraction for the tourist. )

You could make this a long days drive from NYC and finish in Philadelphia or Baltimore for a couple nights. Philly is a larger city with Revolution-era historical sites (like the Liberty Bell); Baltimore has a great walkable city center right on the water (museums, boats).

Then proceed to Washington DC. There is plenty to see here, and you can take day trips to the surrounding countryside (like Mount Vernon, George Washington's home, or Annapolis, with a grand harbor area).

Its a start ...

Do you like hockey?

Washington Capitals -- Alex Ovetchkin, Russian superstar.

NY Rangers
NJ Devils
Philadelphia Flyers
Hershey Bears (minor league)

Many thanks to everyone for very useful answers!