My major hobby is windsurfing. If you are one of those people who see windsurfing and say to yourself, "I must try that one day", then do it now. You'll have fun straightaway and it will hold your interest because there is always that next step.
You don't need exceptional balance either, if you can ride a bike then you will quickly learn to stay on a board.
The best way to start is to attend a training course. Here in the UK the Royal Yacht Association (RYA) runs an excellent 5 level training scheme with good quality instruction backed up with books and videos.

 wave ride Slide Show

air time