Sesame Street and The Land Before Time/Dr. Seuss

Version 1

 * Big Bird (from Sesame Street) as The Cat in the Hat
 * Snuffy (from Sesame Street) as Thing 1
 * Oscar the Grouch (from Sesame Street) as Thing 2
 * Kermit the Frog (from Muppets) as Norval the Fish
 * Cera (from The Land Before Time) as Sally
 * Littlefoot (from The Land Before Time) as Conrad
 * Robin the Frog (from Muppets) as Nick
 * Elmo (from Sesame Street) as Little Cat A
 * Ernie (from Sesame Street) as Little Cat B
 * Bert (from Sesame Street) as Little Cat C
 * Cookie Monster (from Sesame Street) as Little Cat H
 * Little Bird (from Sesame Street) as Little Cat N
 * Fozzie Bear (from Muppets) as Little Cat Z
 * Frazzle (from Sesame Street) as The Grinch
 * Barkely (from Sesame Street) as Max (The Grinch's Dog)
 * Grover's Mommy (from Sesame Street) as Cindy-Lou Who
 * Gonzo (from Muppets) as Sam-I-Am
 * Grover (from Sesame Street) as The Grouchy Guy/Joey (Sam-I-Am's Friend)
 * Daddy Topps (from The Land Before Time) as Mr. Brown
 * Ozzy (from The Land Before Time) as The Lorax
 * Kosh (from The Land Before Time) as Fox in Socks
 * Iguanodon (from The Land Before Time) as Mr. Knox
 * Velociraptors and Fast Biters (from The Land Before Time) as Sneetches
 * Pteranodons (from The Land Before Time) as Wickershams
 * Count Von Count (from Sesame Street) as Yertle the Turtle
 * Amazing Mumford (from Sesame Street) as Thidwick the Moose
 * Grandpa Longneck (from The Land Before Time) as Horton the Elephant
 * Rhett (from The Land Before Time) as Morton the Elephant Bird
 * Hyp and Mutt (from The Land Before Time) as North Going Zax/South-Going Zax
 * Grandma Longneck (from The Land Before Time) as Jane Kangaroo
 * Shorty (from The Land Before Time) as Junior Kangaroo
 * Rooter (from The Land Before Time) as Vlad Vladikoff
 * Bron (from The Land Before Time) as King Derwin

Version 2 (made by Sesame Street and Dinosaurs)

 * Big Bird as The Cat in the Hat
 * Snuffy as Thing 1
 * Oscar the Grouch as Thing 2
 * Little Bird as Norval the Fish
 * Cera as Sally
 * Littlefoot as Conrad/Nick
 * Elmo as Little Cat A
 * Ernie as Little Cat B
 * Bert as Little Cat C
 * Cookie Monster as Little Cat H
 * Robin the Frog as Little Cat N
 * Fozzie Bear as Little Cat Z
 * Kermit the Frog as The Grinch
 * Rowlf the Dog as Max (The Grinch's Dog)
 * Miss Piggy as Cindy-Lou Who
 * Gonzo as Sam-I-Am
 * Grover as The Grouchy Guy/Joey (Sam-I-Am's Friend)
 * Daddy Topps as Mr. Brown
 * Ozzy as The Lorax
 * Kosh as Fox in Socks
 * Iguanodon as Mr. Knox
 * Velociraptors and Fast Biters as Sneetches
 * Pteranodons as Wickershams
 * Amazing Mumford as Yertle the Turtle
 * Count Von Count as Thidwick the Moose
 * Grandpa Longneck as Horton the Elephant
 * Rhett as Morton the Elephant Bird
 * Hyp and Mutt as North Going Zax/South-Going Zax
 * Grandma Longneck as Jane Kangaroo
 * Shorty as Junior Kangaroo
 * Pat as Vlad Vladikoff
 * Bron as King Derwin
 * Elsa as Mom
 * Littlefoot's Mother as Kathy (from In Search of Dr. Seuss)