DC / Max Fleischer
When you think how long Superman has been around you'd be forgiven when assuming a 1940's cartoon would do no justice to the character. However, in my opinion the style of animation has been on par (if not better) than more recent attempts.
Here's a link to the first episode to the first Superman cartoon series back in the 1940's, see what you think.
Come on admit it, it's not bad at all for a cartoon made over 70 years ago!