Aaron Seltzer and Jason Friedberg are not unlikely the most hated directors/writers of all time, but you have to see that they are making parodies. A parody never tries to be something big (even if it is named "Epic Movie"), it wants to entertain and not more.
Also, a parody usually borrows the plot from the original movie, so you can not say that it is cliched or has a bad plot.
I think that "Epic Movie" has its funny moments - for example the Kribbs spoof - but it is not as good as their previous comedy "Date Movie". Some jokes seem to be overused, like the part where Lucy's tongue is frozen to the pole.
Overall, it is enough for an evening of entertaining and there are much worse movies: those who think they are big, but end up unintentionally funny.
The movie has some violence, but it is slapstick-like.
Characters get hurt, sometimes in a way that would cost them their lives - but in the next scene they are unharmed.
A man's arm is broken and an obviously fake bone is sticking out.
A girl's head is kicked off (no blood, she comes out unharmed and has the head back in the next scene).
A girl's tongue is ripped off (no blood, the obviously fake tongue is seen frozen to a pole).
Several characters fight in a battle and are killed with axes, arrows, swords, etc.
I don't rememeber anything bloody in this movie.
In the PG-13 version of the movie, the sexual references are frequent, but nothing too explicit is shown.
In the Unrated version, there is one scene of full frontal female nudity (in the PG-13 version she wears underwear), but not in a sexual context.
You see a man in bed with a woman. She wears underwear in the PG-13 version, but her breasts are visible in the Unrated.
Otherwise, the sexual content is equal to the PG-13 cut.
There are references to beastiality.
The language is average in the PG-13 version, but the Unrated version has an extended scene in which "motherf*****g" is said several times (it is "goddamn" in the rated version).
A sequence features a girl drinking a very large amount of alcohol, she then heavily vomits (this can be seen in both versions, but it is longer in the Unrated version).
Should be okay for teens and up.