I'm guessing you are landing at BWI? Your best bet is
cruiseamerica.com. It is located in Towson so you'll have to take a cab to get there.
You'll definitely want to stop in DC though you could spend your entire week there. If you are short on funds,
Greenbelt Park is great.
From there, I would take the beltway (495) to Route 66W to head into Virginia and
Shenandoah National Park. Big Meadows is still open at that time and you may catch the end of leaf peeping season.
From there, I would head down Route 81 to Tennessee. You can go to
Great Smoky Mountains National Park or head toward Nashville.
