Explorer Dan Buettner is one of the world’s leading experts on the longevity habits of some of the healthiest people on Earth. Now, he’s sharing what’s he’s learned about the happiest people in the world.

Her catchy ode to roller skates made her the No. 1 female vocalist in the early 1970s, but Melanie says it’s taken her years to realize that it’s OK to be a little cute. She reveals how her song “Brand New Key (The Roller Skate Song)” inspired Elton John to write one of his biggest hits.

Wouldn’t it be great to make a living doing exactly what you love? Or to make a difference in your community? You’ll meet an eclectic mix of people doing just that, from a 104-year-old artist to a 50-something skydiving legend to a Rock and Roll Hall of Famer. They share one thing in common — they’re not afraid to change their dreams. (Click here to watch the video version of this story.)

It’s hard to say that a 109-year-old died too soon. But Ruth Hamilton was always up for new adventures. It’s why she became the world’s oldest blogger. You’ll be touched by her story and her legacy. (Click here to watch the video version of this story.)

Since 1968, legendary track and field coach Brooks Johnson has had at least one athlete in every single Olympic Games. And his streak may continue in 2012. He offers tips for anyone, no matter their talents, looking to live up to their potential in life.