I commuted from Pax to Va Beach for 10 years, every weekend. Hands down, Rt 17 is the best route. Sometimes 95/64 is quicker but 17 is a much nicer ride and always traffic free. 95/64 is especially bad in the summer with the bluehairs and their motorhomes and the family trucksters headed to the coast resorts.
Our daughter attended The College of William & Mary in Williamsburg for 4 years and we go to Virginia Beach quite often. I totally agree with everyone, Rt. 17 is the way to go any time of day or night. If you see more than half a dozen cars on the more rural parts of the drive, that is a lot of traffic. Take the right onto Rt. 33 Westbound through West Point and left on Rt. 30. Then you can either take I-64 to get right to Williamsburg or stay on Rt. 30 which runs right into Rt. 60 to go through Lightfoot and the little towns there (more shopping) on the way into Williamsburg.