I don't know what to choose. Ripstiking, Waveboarding or Skateboarding?

I've always wanted to learn how to do all these stuff! But I need to choose only one. What's the easiest to learn? Can I teach my dog to do that sport? Is it a practice for snowboarding? I've always wanted to snowboard when we get to Japan. But I'll need some practice here in the Philippines first (There's no snow here in the Philippines). Can kids 9 years old and up do that sport?