Rockman Hoshi ni Negai wo

Both are based off of video games, but they turn out to be real. 

Both are short and fun little OVAs based on video game series that take a few liberties with them while still remaining very faithful to their source materials as well (although Mega Man is much more educational than Sonic, still enjoyable for older viewers) 

If you want to learn more about Japanese culture and traditions, those shows are for you. Nihon no Mukashi Banashi will tell you the folktales through short stories that everybody can enjoy without any knowledge of Japan, and those OVA of Rockman/Megaman make you discover the Japanese lifestyle, their customs and festivals. They're also both accessible to children as well as adults.