5. Fantastic Four
If there's one thing we learned from the Fantastic Four movie and its sequel, Rise of the Silver Surfer, it's that the Fantastic Four just won't work on the big screen. The reason for that is this; they aren't joke characters and they aren't meant to be cheesy but, given their powers and their names, it's virtually impossible to make them seem anything but. Mister Fantastic, the Invisible Woman, the Human Torch and the Thing just can't be taken seriously - especially when their powers include being able to stretch and being very rock-like. This is definitely one set of superheroes that should be restricted to their source material. Keep them in the comics please, Marvel/Fox (sadly, it seems as though a reboot is on the cards, however).