For just fooling around (entirely non-sexual)...
I live near a couple of pretty nice lakes, and a few years ago I bought an Ocean Kayak Malibu Two, a two-person (three, in calm water) sit-on-top. It's a great recreational boat, stable and safe for the kids (they were in high school then; out of college now), and I've used it a couple of times in the ocean at Monterey, where it's bog slow and gets blown around by the wind a lot (you stick up pretty far, and it's got a wide, fairly short hull). A lot of fun if it's what you want, but definitely not a racer or whitewater boat.
I also have a Pongo 140 I got for Father's Day last year, a 14-foot sit-inside that I haven't used much yet. It's much faster than the Malibu and less subject to wind, because you're inside the boat and present a smaller surface. I'm a sub-average paddler and haven't had it in any kind of serious water, but a friend who has lots of experience (done Class V rapids in Chile and runs big surf in his own Dagger) said it would work well in the surf and pretty well in Class II-III. It's not suited for a lot of the little niggly, rocky rapids around here...but neither am I. Soon as things warm up a little, we're going to take both of them to Sacramento and find a place to put in where we can do an all-day drift down the river. I used to do that in canoes when I was a kid, and it was a lot of fun.
