I love, love, love road trips. All of DH’s and my vacations tend to involve long drives! Excuse me for geeking out about this a little bit, but I have suggestions for you 🙂
Do you want to do a long haul with minimal stops to get somewhere new? Or do you want to do lots of stops along the way?
If you’re heading south from NYC, for example, you could stay on 95 (which is not pretty) but it’ll take you through Philly, D.C., and on to Savannah, etc., and you can take a couple hours detour off to stay a night or two in Virginia Beach or the Outer Banks or something like that. A fun trip might be to leave from NYC, do lunch and maybe a museum in D.C., head on to Virginia Beach for dinner and an overnight, then on to Savannah the next morning and stay there a couple days.
Alternatively, for a scenic drive, you could head for the Skyline Drive like LadyBear suggested, or the Blue Ridge Parkway, which is further south and goes through the Blue Ridge Mountains and Great Smokey Mountain National Park. It takes about 6 or 7 hours from NJ to the start of Skyline Drive in Shenandoah National Park, if I remember right, and then Skyline Drive is quite long. It’s also entirely within the park, so if you’re looking for a city atmosphere it might not be a great choice. But there’s camping or a couple lodges within the park if you wanted to stay there.
My sister and I recently drove from the east coast to San Diego, which was a blast. We took 9 or 10 days, I think, to head out there (one way, she stayed there and I flew home) and went through the Badlands in SD, Mt Rushmore, Yellowstone, a bunch of the National Parks in Utah and the Grand Canyon. Definitely worth it, but a long trip. West of NYC there’s not all that much to see until you really start to get west of the Mississippi, so unless you’re interested in a substantial trip I’m not sure you’d want to head that way.
Anyhow, I’ll stop there. I think you’ll have fun, whatever you decide to do!