The obvious difference is of course the time period in which it is set. Some other differences are 1) In Act I, the dialogue between the Montagues and Capulets is reversed; the Montagues say the Capulet lines, the Capulets say the Montagues lines; 2) The Nurse's conversation with Juliet about Romeo is cut short. The part about Faith is left out; 3) The timing and location for the death scene is off. Juliet should have awoken hours, not seconds, after Romeo died; 4) the prologue is shortened in the movie.