I think anyone who's watched Mystery Sceince Theater 3000 knows too many bad movies. Some of the more memorable episodes are Manos: The Hands of Fate, The Deadly Mantis, The Final Sacrifice, Hobgoblins, Overdrawn at the Memory Bank, and The Wierd Creatures That Stopped Living and Became Mixed-Up Zombies.
Also, The Lighting Theif and A Series of Unfortunate Events are bad on a personal level in that they completely trashed the book/books they were based off of. Not to mention that both movies are based off of my favorite book titles.
Birdemic is also a stink bomb in its own way. as well as Santa Claus and the Ice Cream Bunny.
I HATE March of the Penguins. Also, M. Night Shamalans rendition of Avatar. It wasn't too bad itself if you watched the show, but it certainly didn't capture the characters of the show well, or even pronounce the names right :/