Dune is probably the most difficult book I've read so far. It's not that it's boring, theres just SO MUCH STUFF. I would read thirty pages and have to stop to sort it out. However it is still one of my most favorite books EVER
Boredom wise, I'm going to have to say To Kill a Mockingbird, anything we had to read by Hemingway, and Adventures of Huckleberry Finn. *shudder* I never finished TKAM(i did get full marks on a project i bullshitted my way through for that one), what little we read in class by Hemingway had such beige prose it was boring, and Huckleberry Finn ... is just plain boring. I mean, lots of shit happened, but I couldn't get past the narrator. AGHH
I must say I actually liked Gatsby. It was a decent movie too.