Do whatever you can to avoid I-95 through Northern VA (Richmond to NVA) on the weekends or during traditional rush hour. Keep in mind that this warning actually extends through DC and into Southern MD and includes the beltway.
If you are not going to hit Fredericksburg or Manassas for civil war interests, or take a peek at Yorktown or Williamsburg. Good alternate routes through VA are 13 on the Eastern Shore (DelMarVA Peninsula), US 17, or 301.
If you opt for 95 through VA anyway, there is a nice KOA just north of the Thornburg Exit, and a Walmart that accepts overnight campers at the Spotsylvania Exiit. Either one may be a good stop off if you hit the traffic. Hope you have a great trip!