I don’t know if I have any records from pre-2001!
Fourth (2001): Robots: Smurfs (Gargamel’s Puppet); Mighty Orbots; Herculoids (Mekkor); Astroboy; Thundarr the Barbarian (Fortress of Fear); Battle of the Planets (Spectra’s Space Spider); Superfriends (Trial of the Superfriends); Frankenstein Jr; Transformers (Fire in the Sky); Big Guy & Rusty the Boy Robot; Powerpuff Girls (Uh Oh, Dynamo); Jonny Quest (Robot Spy); The Tick (Armless But Not Harmless); Bugs Bunny (Hair-Raising Hare); Spider-Man (Captured by J Jonah Jameson); Superman 1941 (Mechanical Monsters); Futurama (Fear of a Bot Planet)
Fifth (2002): Secret Origins: Star Trek Animated (Yesteryear); Jonny Quest (Calcutta Adventure); Dungeons and Dragons (Treasure of Tardos); Spider-Man (Origin of Spider-Man); Ripping Friends (Stinky Butt); Big Guy and Rusty the Boy Robot (Creatures Great and Small); Powerpuff Girls (Mr Mojo’s Risin’); Freakazoid! (The Chip); The Tick (Tick vs The Idea Men); Battle of the Planets; Bugs Bunny (Herr Meets Hare); Justice League (Secret Origins)
Sixth (2003): Supernatural: Thundarr (Brotherhood of Night); Jonny Quest (Monster in the Monastery); Superman 1941 (Mummy’s Curse); Star Trek (How Sharper Than A Serpent’s Tooth); Superfriends (Swamp of the Living Dead); Real Ghostbusters (Citizen Ghost); Dungeons & Dragons (Day of the Dungeon Master); Scooby Doo; Birdman; Harvey Birdman Attorney at Law; Battle of the Planets (Space Mummy); Spider-Man (Witching Hour); Samurai Jack (Jack and the Archers); Powerpuff Girls (Boogie Frights); The Tick (HEROES); Freakazoid! (Tomb of Invisibo); Dexter’s Lab (Filet of Soul); Rocko’s Modern Life; Ren & Stimpy (Littlest Giant)
Seventh (2004): Doppelgangers: Star Trek (The Survivor); Dungeons & Dragons (Garden of Zinn); Jonny Quest (Double Danger); Big Guy (1000 Fingers of Rusty); Superfriends (Wanted: The Superfriends); Superman 1941 (Showdown); Superman 1997 (Identity Crisis); Ripping Friends (Manman & Boyboy); The Tick (The Tick vs The Tick); Futurama (Farnsworth Parabox); Sealab 2021 (Lost in Time); Powerpuff Girls (Powerpuff Bluff); Spider-Man (Double Identity); Clone High (Litter Kills–Litterally); Samurai Jack (Jack vs Mad Jack); Aqua Teen Hunger Force (Moonenites); Justice League (A Better World); Freakazoid
Eighth (2005): Outer Space: Ren & Stimpy (Space Madness); Fantastic Four (Galactus); The Tick (Alone Together); Disney (Life on Mars); Big Guy (Birthday Bash); Superfriends (Man in the Moon); Star Trek (Slaver Weapon); Bugs Bunny (Haredevil Hare); Home Movies (History); Captain Star (The Worm Turns); Futurama (Where No Fan Has Gone Before); Duckman (Where No Duckman Has Gone Before); Simpsons (Deep Space Homer); Venture Brothers (Careers in Science); Real Ghostbusters (Ain’t NASA-sarily So)