Luhrmann and Zeffirelli take significantly different approaches in staging one of the most famous scenes ever written by Shakespeare and some of the most iconic lines in all of English literature. In the Zeffirelli film, Romeo, played by Leonard Whiting, is a much more passive character. Though he climbs the orchard walls, he lingers in the bushes, physically separating himself from Juliet until she fully reveals her complete devotion to him: "Romeo, doff thy name/ And for that name, which is no part of thee/Take all myself" (II.ii.49-50). It is only at this moment that he comes forward.
Conversely, in the Luhrmann interpretation Romeo is portrayed as bold and confident. He not only dares to breach the walls of the Capulet household, but he positions himself directly under Juliet's window. Rather than having Romeo stay still throughout Juliet's soliloquies, Luhrmann escalates the tension by having Romeo move closer and closer to Juliet until he becomes almost a shadow of her. (In fact, Romeo's haste has him running into furniture and knocking objects over - his passion and daring continues to put him in greater jeopardy.) Though Romeo doesn't fully reveal himself until Juliet's grand offer of "all myself," by then his verbal admission of his commitment to her is a mere formality. He has proven his devotion through his wreckless abandonment of any safety and security for his own person.
This boldness also affects how other characters interact with each Romeo. In the Zeffirelli production, Juliet becomes the dominant character. She is literally above Romeo for most of the scene. In the Luhrmann production, however, he levels this power structure by bringing Juliet down from her balcony. Her enthusiasm springs from Romeo's rather than acting as a catalyst to embolden him as in the Zeffirelli interpretation. Similarly, when Leonardo DiCaprio makes the conscious decision to jump out of the Montague car, Mercutio and the other members of the entourage see where he is going and understand the consequences his boldness might have. Their taunting is a failed attempt to dissuade him from his wreckless behavior. In the Zeffirelli version, Romeo's friends do not observe him scaling the orchard wall. Thus, the mocking Romeo experiences from his cohort doesn't represent an attempt to alter his actions but is rather a reaction to his continued moping and gloominess.