Casey Kasem as Shaggy (archive footage) (uncredited)

Sandy Duncan as Self

Davy Jones as Self

Tim Conway as Self

Phyllis Diller as Self

Jonathan Lipnicki as Self

Tom Kenny as Mayor of Townsville - Top Cat (voice)

Jeff Bennett as Johnny Bravo (voice)

Ron McClary as Captain Linger (voice)

Don Knotts as Self

Jonathan Winters as Self

Robin Williams as Self

Marsha Crenshaw as Announcer (voice)

Arthur Anderson as Eustace Bain (voice)

Doug Preis as Thundarr the Barbarian (voice)

Janet Waldo as Judy Jetson (voice)

Thea White as Muriel Bain (voice)

B.J. Ward as Betty Rubble (voice)

Jennifer Martin as Miss Sara Bellum (voice)

Charlie Adler as Big Red Guy - Chicken (voice)

Grey DeLisle as Daphne Blake (voice)

Caroline Sellers as Wilma Flintstone (Young) (voice)

B.J. Mitchell as Barney Rubble (Young) (voice)

Tom Kane as Professor Utonium - Him (voice)

Brenda Vaccaro as Bunny Bravo (voice)

Jeff Bergman as Porky Pig - Fred Flintstone / Foghorn Leghorn / Elmer Fudd (voice)

Debbie Allen as Self (uncredited)

Christina Augustinos as Producer (uncredited)

David-Paul Grove as Johnny 2x4 (voice) (archive footage) (uncredited)

Kathleen Barr as Kevin (voice) (archive footage) (uncredited)

Mel Blanc as Bugs Bunny (voice) (archive footage) (uncredited)

Christine Cavanaugh as Dexter (voice) (archive footage) (uncredited)

Keenan Christensen as Jimmy (voice) (archive footage) (uncredited)

Kat Cressida as Dee-Dee (voice) (archive footage) (uncredited)

Eddie Deezen as Mandark (voice) (archive footage) (uncredited)

Patrick Ewing as Self (uncredited)

William Hanna as Self (archive footage) (uncredited)

Matt Hill as Ed (voice) (archive footage) (uncredited)

Scott Innes as Scooby-Doo (voice) (uncredited)

Janyse Jaud as Sarah (voice) (archive footage) (uncredited)

Chuck Jones as Self (archive footage) (uncredited)

Peter Kelamis as Rolf (voice) (archive footage) (uncredited)

Chris Kirkpatrick as Self (uncredited)

Don Messick as Scooby-Doo (voice) (archive footage) (uncredited)

Tony Sampson as Eddy (voice) (archive footage) (uncredited)

Sam Vincent as Edd (voice) (archive footage) (uncredited)

Frank Welker as Fred Jones (voice) (archive footage) (uncredited)