It's my understanding that Virginia Landing is a good 45-50 minute drive to get to the ocean. It's misleading when you look on the map. I've heard it's a nice park, though. Seems best suited for folks who want to go fishing.
Of the Virginia parks, I've only been to Harborview and Williamsburg.
Harborview is a cute park, but there's not a whole lot in the area. You need to go with the plan to be camping and just hanging out. The little town of Colonial Beach is cute, but there's not a whole lot to it. George Washington's birth place is nearby and I know friends went and said that was fine.
You CAN technically tour DC from there, but figure on 2+ hours to get into the city depending on how you go. Especially if you take mass transit.
Our spot was strangely huge in it's layout:
And here was an interesting rig and another spot in the park:
Williamsburg is the opposite. To me, the park is just so/so but it did have an indoor pool if you do want to go swimming. But the area is rich in history. We went there for spring break back in 2013 or 2014 and then again just last September.
I didn't get a good shot of our campsite this past visit, so here's a crappy view of it. We were in an outer edge of the park that was a little more spacious than the rest of the park. However, there was a bit of a hill getting into our site. Once we got past that, it wasn't bad. We were under a tree and squirrels would chuck stuff at the camper and us.