Superman X/Superboy/Conner Kent as Bambi
Flash/Kid Flash/Wally West as Thumper
Nightwing/Robin/Dick Grayson as Flower
Raven as Feline
Jinx as Thumper's mate
Starfire as Robin's mate
Lois as Bambi's mother
Superman as The Great Prince
Batman as Friend Owl
Flash/Barry Allen as Thumper's father
Iris West-Allen as Thumber's mother
Darkseid as Man
Lana Lang as Mena
Beast Boy as the porcupine
Instead of a forest, this takes place in Metropolis and Gotham.
Also, Kid Flash is raised by his aunt and uncle instead of his parents.
Instead of man being the main threat, Darkseid is.
Also, as Robin isn't a skunk, he doesn't do hybernation.
Also, the other two mates of the three friends are given more emphasis in the story.
Finally, while there isn't one in the film, Superboy and Superman have a confrontation with Darkseid.
In Conner II, instead of going to see the groundhog, the kids go to see Green Lantern.
Also, the porcupine character is a young boy made into a friend instead of being a grumpy old man.