Kings Dominion is the only theme park I've ever been to. I've been there a few times, but while I love watching coasters and I grew up playing RCT for hours and hours on end, when it comes to riding them, I'm a huge chicken. Still, there's a lot to do, and quite a bit of other rides that I will ride.
Busch Gardens is actually closer to me than KD, but I've never been there. From what I've heard it's better in terms of scenery and stuff, but KD beats the crap out of it in terms of rides.