My idea of a good time.....
Hardware Wars
Godzilla vs. Bambi
Manos, the Hands of Fate
I second 'Motel Hell'
'Robot Monster'
"Monster Shark vs Giant Squid" (The shots of the US submarine fleet rushing underwater in close formation was enough for my, besides the sheet metal shark fin)
Any Ed Wood movie. (Glen or Glenda is up there)
Bucket of Blood (would you probe around for a cat stuck in the wall with a big knife and what do you do with old girlfriends)
Team America: World Police (done with marionettes. See the unrated version for pete's sake)
Teenagers from Outer Space (The MST3000 version)
Reefer Madness
Anything by the Zuckers, especially Kentucky Fried Movie (esp. 'Fistful of Yen', 'Catholic High School Girls in Trouble, 'The Sex Record', 'Scot Free', 'That's Armageddon', 'United Appeal for the Dead', 'Zinc Oxide' and 'Eyewitness News. 'Airplane!' was genius. 'Top Secret' was superbly stupid.
The Groove Tube
Was Animal House stupid? Whatever it was hilarious
Wayne's World
This is Spinal Tap
The Killer Shrews (dogs with patches of hair pasted on)