There are a couple things right off the bat. These movies are going to be SUPERHERO movies, not just comic book movies. For the movie to be considered for the list, they have to have some extraordinary power. Batman, therefore doesn't count, because being disgustingly rich doesn't count as a super power. However, Green Lantern would, as his ring, while essentially a gadget, still bestows upon him some pretty amazing powers. Also, this time I am limiting myself to just 5, with perhaps a dishonorable mention section afterward. And for a final bit, I will be putting these in order of offensiveness... Least offensive of the 5 at the top, and the worst of the worst at the bottom.
5) Superman 3- This one was a train wreck from the beginning. Taking the good will earned from 2 rather decent films, and then stomping all over it with a weak story, and an unfortunate cyber-terrorism story that would have been more up Iron Man's alley. Richard Pryor's comedic style was an ill fit for the somber attitude of Superman, and rather creating a sort of comic foil, it created a grating mishmash of uneven tones that there was no hope of recovering from.
4) Fantastic 4: Rise of the Silver Surfer- A sequel to a bad movie, is rarely a good idea. Sure, there were some somewhat campy fun moments in the first film, but not enough to warrant a sequel. This film, took the stupidity of the first film, and expanded upon it. Snowballing from the beginning into a place that just felt like the beginnings of a migraine. The only good thing that can be said for this movie, is that the studio learned from it, and never went ahead with a sequel. Here's to hoping that Marvel gets the rights back, and can actually do this property some justice.
3) Spider-Man 3- Sometimes a movie's stupidity, isn't always the fault of the director. Sometimes it is the fault of the studio. In this case, I think both parties might have to share the blame. Sure, the studio may have insisted on the addition of fan-favorite villain Venom, but Raimi's handling of the addition of that character was almost unbearable to watch. From dancing Peter Parker, to the woefully miscast Venom, this movie lacked the heart of the first two films.
2) Ghost Rider- If you know me, you know by now, that I loathe just about everything that Nic Cage has ever done... except for Kickass, a movie that actually played well with Mr. Cage's over-acting. With Ghost Rider, his acting didn't fit, and his age made the character more unbelievable, considering the character is a biker with a flaming skull, making him more unbelievable is an almost laudable achievement. The movie could have been a glorious bit of camp, instead it was a mess of ham-fisted line delivery, and an over-abundance of villains. Too bad they didn't just let this one go up in flames.
1) Green Lantern- For me, this movie is the single worst representation of a superhero movie ever. Miscast at almost every level. Incoherent story. Unsympathetic characters. Oh yeah, and the main villain of the piece, is a giant yellow blob of shit! ...Actually, that last one is rather appropriate, since the movie itself is a steaming pile of shit. Just one example of the problems in the casting department: Ryan Reynolds (36), Blake Lively (25), and Peter Sarsgaard (41) are all supposed to be the same age? Peter actually looks OLDER than the man who is supposed to be playing his father. Incoherent story, you ask? How about having an untrained rookie defeat an ancient entity, that even the people who created his powers couldn't defeat? The sole shining point in this entire film, was Mark Strong's Sinestro... But that was not enough to take this film and make it worth your time. This movie, was so bad, that I use it now as my litmus test. Whenever I see a movie that was bad I ask myself..."Sure, it was bad... But was it 'Green Lantern' bad?" This load of shit, was a waste of time, and I will never get those 2 hours I wasted on it back...
Dishonorable Mention (Items excluded from the list above, for space purposes, or because they didn't meet my criteria): Steel, Elektra, Catwoman, Batman and Robin, Superman 4, Superman Returns, Fantastic Four, X-men: Last Stand.