Doug (the one from Nickelodeon) was an very good series. It was the first time I heard the voice talent of Billy West. The stories were meant to teach morals. And it was fun too, it was like nothing I'd seen before.
Now Disney's Doug start out where Nick's left. And it was a product of inferior quality. Many original voices were replaced and much of the charm of the original was lost.
4 stars from the original + 2 from Disney's gives an average of 3 stars.