1. Tim Curry as Nigel Thornberry
2. Jessica Walter as Fran the Dinosaur
3. Alexander Gould (aka Shane Botwin) as Nemo
4. George Clooney as the doctor from South Park.
5. Michael Cera as Brother Bear
6. Bruce Willis as Spike
7. Robert Downey Jr. as Patrick Pewterschmidt
8. Carlos Alazraqui as Rocko
9. Justin Timberlake was the guy who said "I'm lovin' it" in the McDonald's commercials.
10. Busta Rhymes as Reptar
The Rugrats Movie
11. Frank Zappa as the pope in Ren and Stimpy
Ren and Stimpy
12. Uncle Phil from Fresh Prince as Shredder
13. Jay Leno as The Crimson Chin
Fairly Odd Parents
14. Alec Baldwin as the bad guy Dennis
The SpongeBob Movie
15. The voice of Lilo is the girl from The Ring.
16. Michael J. Fox as Stuart Little
17. Vin Diesel as The Iron Giant
The Iron Giant
18. Whoopi Goldberg as Fantasy the Book
19. Mel Gibson as John Smith
20. Val Kilmer as Moses
The Prince of Egypt
21. Burt Reynolds as Charlie B. Barkin
All Dogs Go to Heaven
22. Dustin Hoffman as Benedict Arnold
23. Adam West as R. Kelly’s Lawyer
24. Stephen Colbert And Steve Carell As The Ambiguously Gay Duo
25. Kurt Russel as Elvis in Forrest Gump
Also not a cartoon. But let's just go with it.
26. Ringo Starr as the Duck Brothers
Courage the Cowardly Dog
27. J.K. Simmons as the yellow M&M
28. Flea as Donnie
The Wild Thornberrys
29. Jeff Goldblum voiced the villain Verminous Skumm.
30. Meg Ryan was Dr. Blight.
31. And Sting was Zarm.