I have never jumped out of a plane, though I always wanted to. My right ankle was very badly sprained in a skiing accident years ago, so it's not in the best shape, and that always gave me second thoughts.
White-water rafting is actually very safe as long as you use the required floatation, helmet, etc, and wear a wet-suit when the water is very cold. We have some really nice class IV-V rapids, and for years I spent many of my spring-though-fall weekends kayaking and canoeing those rivers. As long as you can eskimo-roll or at least self-rescue it's pretty safe. The most dangerous times are when you're fooling around in the rapids and flip. For a second or two (before rolling back up), you're upside-down with rocks sailing past (hopefully!) your head.
My younger brother worked as a photographer for a business that sold video-tapes, slides, etc to rafters and as soon as the water level came up, he'd jump in the river with his waterproof gear box and run the Kennebec Gorge rapids with an inner tube to get to a good vantage point to take pictures of tourists in some big rapids. Eventually, the rafting outfitters made his boss forbid him to do that. The rafters had often paid $75 or more each for what they thought was a thrilling dangerous ride down the gorge and it kind of blunted their experience to watch a teen-ager run the gorge with an inner tube and a life jacket.
