Christine R.
Yelp
This festival of absurd and wonderful theatre is so much fun - even if you end up at a sucky show or two. But when you find a great one - trust me, lines from it can stay with you for years. One show I saw eight years ago (8!) called "Labrador" still sticks with me. The performer, TJ Dawe, is still performing, directing, and writing new shows at the Fringe, and he's a pretty reliable Fringe pick (go see Totem Figures, playing at Havana Restaurant.)
Otherwise, it's fun just to go down to Granville Island during the Fringe with no particular ideas, and just see whatever is playing or whatever looks good. If you make a night of it, you can probably cram in about three shows, two with a dinner/drinks break. Shorter shows are about 20-30 minutes, longer shows run up to an hour or an hour and 15 minutes.
If you really, really want to see something, advance tickets are a good idea, but every venue holds back some tickets at the venue, and the box office for each show open 50 minutes before the performance. I made the mistake of waiting til after dinner to purchase tickets for one show, and by the time I got there, they were sold out. Who knew a play about socks in the dryer (yes, socks) would be so popular?
PS Experimental theatre may not be suitable for kids. It can be raw stuff. But you'll probably laugh, perhaps even if it's not a comedy...