Welcome aboard the RoadTrip America Forums!

Let's start with a little background reading for some of the different segments of your trip:
Washington to New England via New York State
New England

For a good scenic route from south-central Pennsylvania up into New York State and the Finger Lakes, you'd be hard pressed to do better than US-15 up the Susquehanna River Valley. From the Finger Lakes into northwestern New England, look at I-88 and NY-22 and plan on taking one of the ferries across Lake Champlain. As I've stated often, it's tough to find a non-scenic road in New England, but some particularly nice ones are VT-100, NH-112. ME-113, and US-1 along the coast between Newport and New Haven.

You've got plenty of time to work out the details, so once you've ingested all of the info above, we'll be more than happy to answer any further questions you might have.

AZBuck