Thank you, thank you, thank you, Rob. I have never understood the fascination with Napoleon Dynamite. I, however, didn't have the option to turn it off, but instead had to leave the room after 30 or so minutes. I opted to watch paint dry instead.
I've never walked out of a theater, but would have if I could during the inane Drew Barrymore vehicle Driving in Cars with Boys. Ugh, that was awful. I should've totally known what to expect (and I probably did), but my girlfriend at the time really wanted to see it, and...well, you gotta do what you gotta do.
As for rentals, I've slept through too many to count. The last ones to put me to sleep were Synecdoche, New York and The Dark Knight. At least I'm consistent, since I snoozed during Batman Begins, too.