Scooby Doo
No matter where you are from or how old you are, there is a large chance that Scooby Doo has been part of your childhood. There have been twelve versions of this show, and in 2013, TV Guide named it one of the five best cartoons.
When this show was originally pitched, it was called The Mystery Five. In this first version, Scooby was supposed to be a bongo-playing dog and his mystery-solving friends were part of a rock band. Can you imagine how different this cartoon would have been?