The only films you mentioned that have anything to do with Mythology are the first two.
The last ones don't count, since they are stories that were recently created.
A myth is a story passed down through oral tradition to each generation.
the last 4 you mentioned were only created last century.
Robin Hood, King Arthur, Hercules. These are myths because they are OLD, very old, stories passed down through the years.
And xwolverine2, Xena doesn't count because she never existed before the TV series. She's a new character created for the Hercules TV show.