The Simpsons/Toy Story

Cast

 * Homer as Woody
 * Bart as Buzz Lightyear
 * Principal Skinner as Hamm
 * Moe as Mr. Potato Head
 * Lenny as Rex
 * Chief Wiggum as Slinky Dog
 * Lisa as Bo Peep
 * Smithers as Sarge
 * Thomas (from Thomas the Tank Engine) as Andy (Both young and adult) (There's nothing wrong with using someone for both the young version and adult version of a character)
 * Emily (from Thomas the Tank Engine) as Andy's Mom
 * Mavis (from Thomas the Tank Engine) as Molly (Both young and adult)
 * Mr. Burns as Sid
 * Elizabeth Hoover as Hannah
 * Maude Flanders as Mrs. Potato Head
 * Milhouse Van Houten as Wheezy
 * Marge as Jessie
 * Nelson as Prospector
 * Sideshow Bob as Evil Emperor Zurg
 * Jimbo, Kearney and Dolph as Squeaky Toy Aliens
 * Diesel 10 (from Thomas the Tank Engine) as Al
 * Dr. Hibbert as Mr. Pricklepants
 * Dr. Nick as Buttercup
 * Rosie (from Thomas the Tank Engine) as Bonnie
 * Edna Krabappel as Dolly
 * Luann Van Houten as Trixie
 * Comic Book Guy as Lots-O-Huggin' Bear
 * Sideshow Mel as Ken
 * Elizabeth (from Thomas the Tank Engine) as Barbie
 * Molly (from Thomas the Tank Engine) as Daisy