Eragon
Back when I first saw the trailer for Eragon I declared that it looked like a pile of stacked asses. Now that I have seen the movie in its entirety I can say without hesitation that my first impression was in every respect accurate. We're talking Dungeons & Dragons movie or Uwe Boll levels of bad here. It managed to be not only boring, ugly, and poorly made, but also to exemplify everything that's bad or tired about the fantasy genre. Even the special effects were crap. Only Jeremy Irons managed to dredge anything watchable up out of this mire. Avoid at all costs.