My fondest childhood memories involve shows I saw on television. That might sound sad, but I liked them. In addition to things already mentioned, I'll through in a few things.
There used to be a show I would watch that featured performers dressed as animals. I think it took place in a pet shop and as far as I can remember, it was on TLC in the early 90s.
I also remember loving a show called Under the Umbrella Tree. It was charming. The puppets weren't as great as Muppets, but they weren't without charm... at least I loved them when I was a kid. On the same token, let's not forget Dumbo's Circus, Adventures in Wonderland, and Welcome to Pooh Corner! (Can't you tell I grew up with the Disney Channel as a small child?)
Does anyone remember Sharon Lois & Bram's Elephant Show? It used to come on Nick Jr. when I was a very small child. I remember very little about it, but the song from the end.
http://www.youtube.com/watch?v=9qUAsuRLXig&feature=related If that doesn't give you sugar coated nightmares, I don't know what will.