Well, that was a great vacation! Though I have to mention we were in Virginia for the earthquake and the beginning of Irene, haha. We left Smithfield at 4:30 AM yesterday, headed west all the way to 81 and came north through Pennsylvania to avoid the storm and traffic.
We drove down the way Wally recommended along the coast and on the bay bridge / tunnel. That was really cool! We spent a day at Williamsburg, ended up buying the day pass tickets and we're glad we did. We also did the "ghost tour" at night... it was so-so. Pierce's Pitt BBQ was tasty but it was kind of an "oh, that's it?" experience.
We went to both Virginia Beach and Sandbridge Beach. It was very apparent why "y'all" made the comments you did about each. We are glad we saw Va Beach and the fighters flying overhead, but Sandbridge beach was the most relaxing part of the trip. 
Of all the museums you recommended, we only had time for the air and space center. We got there at opening time and a retired army gentlemen who volunteers ended up giving us a complete, personal tour of the entire building. It was absolutely excellent. We are going to write a letter to the center to thank the volunteer. I cannot recommend this place enough, it was very very cool.
Other things? While staying in Hampton we found the coliseum outdoor mall thing, which was nice to walk around and find places to dine. We liked the colonial parkway drive, took the ferry across to Surry, and stayed in Smithfield for a couple of nights. It was a sleepy town but we just looked at the old homes, pretty scenery and took it easy.
Sorry for the book, but thank you for the recommendations... it helped tremendously and we had a very good time in Virginia!
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