tell her that you would like to see a certain movie and then ask if she'd like to see it too
Just tell her and see what she says
It's just a movie, it's not like you are getting married.
Sure! You can't just wait around and hope you magically end up together...you've gotta make a move. You don't have to ask her to be your girlfriend; just ask her if she wants to see a movie together. The worst she can say is no. You can do it.