As much as I enjoyed many of those, I had to vote for The Elephant Show for one key reason --
-- when I was two (possibly three, or somewhere in between, heck it was kinda blurry), my parents took me to see their touring show when it came to town. According to all retellings of the tale (now that I'm capable of attempting to defend my dignity), I was over the moon with hysterical glee. I also got a chance to see Fred Penner on tour when I was a teenager, and certain aspects of entertainment never really age.
Now I'm on a mental tangent of slightly obscure Saturday morning cartoons. Anyone here remember Botsmaster?
I loved YCDTOTV but an honourable mention needs to go out to Muffy the Mouse and Sam Krenshaw! I remember loving Barbapapa's, Fables of the Green Forest and Jeremy the Bear too. Classic TVO afternoons!!