I posted this on another forum, but if you want a "complete" Scooby collection, this is what you'd have to buy:

TV Shows:
Scooby Doo Where Are You Seasons 1&2
Scooby Doo Where Are You Season 3
The Best of the New Scooby Doo Movies
The Scooby Doo Dynomutt Hour: The Complete Series
Scooby Doo's Spookiest Tales{contains the Scooby Doo Show episode "Vampires, Bats, and Scrardy Cats"}
Scooby's All Star Laff-A-Lympics Volumes 1 and 2{volume 2 is a Target exclusive}
Scooby Doo/Riche Rich Volume 1
Scooby Doo: Winter Wonderdog{contains "A Nutcracker Scoob" and one other Scrappy episode not on a season set}
13 Ghosts of Scooby Doo: the Complete Series{being released at the end of June}
A Pup Named Scooby Doo: Season 1
A Pup Named Scooby Doo: Seasons 2, 3, and 4
What's New Scooby Doo: Season 1
What's New Scooby Doo: Season 2
What's New Scooby Doo: Season 3
Shaggy and Scooby Doo: Get A Clue! Volumes One and Two{no season sets or more volumes being released in the forseeable future}


Movies:
Scooby Doo Goes Hollywood
Scooby Doo{2002}
Scooby Doo 2: Monsters Unleashed
Scooby Doo: The Mystery Begins
Scooby Doo and the Reluctant Werewolf
Scooby Doo and the Ghoul School
Scooby Doo Meets the Boo Brothers
Scooby Doo on Zombie Island
Scooby Doo and the Witch's Ghost
Scooby Doo and the Alien Invaders
Scooby Doo and the Cyber Chase
Scooby Doo and the Legend of the Vampire
Scooby Doo and the Monster of Mexico
Scooby Doo and the Loch Ness Monster
Scooby Doo in Where's My Mummy
Scooby Doo in Pirates Ahoy
Aloha Scooby Doo
Chill Out Scooby Doo
Scooby Doo and the Goblin King
Scooby Doo and the Samurai Sword
Scooby Doo Abracadabra Doo
Scooby Doo's Arabian Nights{though I suggest you skip this one at all costs}



As for Laff-A-Lympics, I'm sure WB will release a season set eventually, but after Shaggy and Scooby Doo: Get A Clue not getting past its second volume, I'm not holding my breath.

WB needs to realize that Shaggy & Scooby-Doo Get a Clue sucked ass and that the original shows are more "loved" by the fans than that piece of garbage.

New Scooby-Doo Movies, The: The (Almost) Complete Collection:
The Best of The NEw Scooby-Doo Movies The Lost Episodes: