Pretty people don't have to be as good as ugly people, but the main reason is so the movie can have a good face to be on the camera.
The Lightning Thief movie has no more roles open. The movie has already been produced, and will be released onto DVD on June 29th, 2010.
yes
I haven't got a clue what you mean by 'dual roles.' More information is needed before your question can be answered sufficiently.
Neil Flynn has played roles such as Janitors, Doctors and TV Fathers. You can get more information about Neil Flynn online at the Wikipedia and Internet Movie Database.
to make more pretty
No. Its more gross than scary. Its a pretty good movie!
A litte more than 20.000 only 114 speaking roles
No, there are more aspiring actors and actresses than will ever be needed which is why it is so competitive for roles.
yeah pretty much, plus a few more
That depends entirely on the type of movie role. For an action or adventure movie, it would probably be a good idea. For a comedy, drama, or period film, then it's not necessary.
to learn more about people without face to face interaction.
Star Wars. Zelda is pretty popular, but there are very few people who haven't watched at least one Star Wars movie.