I can't understand the negativity of some other reviewers here and won't try.
This episode, that I'm watching as I type and have seen before, is brilliant. It so nicely parodies the dreck of Saturday Morning tripe that I grew up with. If not using children's programming to to sell products (Purpleberry Pond), teach lessons via half baked junk (G.I. Joe) they just present a mediocre 'mystery' (Scooby Doo) or adventure that took no effort to think out or write. This episode of Futurama skewers that with plenty of laughs and tongue in cheek references and yes, a few flat out digs at the cliches. For instance, in the Scooby-Doo segment, when Fry and Bendi-Boo run into a room in a hallway of many doors, they don't come out. How often has this gag been beaten into the ground but rarely is it funny (though South Park did a great job of dumping on it!).
Animation, like all TV, can run the gamut of brilliant to nauseatingly bad and sadly, most of the low end over the decades has been aimed at kids. Though this episode is for grown ups, it's the stuff we were subjected to as kids that it makes fun of and I applaud it. Too bad Futurama is now part of the past, because I feel it could have produced plenty more of these critiques of the garbage as it did so well here.