I grew up watching Scooby doo throughout my childhood, even as an adult I still love the show, but my baby brother loves the show now too, which shows its a great show for any and all ages, and stays with you throughout your life.
The show is very engaging as the plot and characters aren't too complex for children, but also aren't too boring and childish for adults.
Episodes move along at a brisk pace - but not rushed.
Recommended!