The play of Romeo and Juliet by William Shakespeare opens with a swordfight in the streets of Verona, Italy between servants and family members of Capulets and the Montagues that occurs at some time in the thirteenth or fourteen century. The movie Romeo + Juliet—adapted from Shakespeare's Romeo and Juliet by Craig Pearce and Baz Luhrmann, directed by Baz Lurhmann, and starring Leonardo DiCaprio and Claire Danes—is set at about the time the movie was released in 1996 and opens with a gunfight between the Capulets and the Montagues. The fight begins at a gas station near a highway off-ramp in Verona Beach, a fictional city resembling Miami, Florida, and ends in downtown Verona Beach.
From a police helicopter hovering over the chaotic scene, the Verona Beach chief of police, Captain Prince—the corresponding character to Prince Escalus in Shakespeare's play—calls down to the combatants over the helicopter's public address system.
CAPTAIN PRINCE. Rebellious subjects, enemies to peace,
Throw your mistempered weapons to the ground.
It's not until the entire opening sequence of the gunfight is over that a voiceover of a slightly shortened version of the prologue of Shakespeare's Romeo and Juliet is heard.
VOICE OVER. Two households, both alike in dignity,
In fair Verona, where we lay our scene,
From ancient grudge break to new mutiny,
Where civil blood makes civil hands unclean.
From forth the fatal loins of these two foes
A pair of star-cross'd lovers take their life;
Whose misadventur'd piteous overthrows
Doth, with their death, bury their parents' strife.
Although the openings of the play and of the movie serve the same purpose—to introduce many of the major characters (except for Romeo and Juliet) and establish the underlying conflict between the feuding families—the differences between the stage version and the movie version reflect the different art forms and the different frames of reference for each type of presentation.
Generally speaking, a play "tells" a story, whereas a movie "shows" a story. Shakespeare's Romeo and Juliet opens with the spoken prologue, in with the Chorus presents a concise narrative of entire story of the play, including the setting "in fair Verona" (Pro. 2), the feuding families and the brawls in the streets (Pro. 1.1, 3-4), the "pair of star-cross'd lovers "(Pro. 6), and their fate: "Doth, with their death, bury their parents' strife" (Pro. 8).
The movie version begins with action, not words, showing a car and a pickup truck speeding down a highway and pulling into a gas station. More vehicles pull into the gas station, and more characters emerge from those vehicles. The characters are gradually revealed to be members of the warring factions of Montagues and Capulets, who become involved in a confrontation that evolves into a full-on gun battle at the gas station that spills over into the city center of Verona Beach.
Both of these opening sequences effectively draw the audience into the play and the movie, as they're intended to do, but whereas it takes several minutes of car chases, gunfights, and hovering police helicopters to establish the background of the story in the movie, Shakespeare does it in the first eleven lines of the prologue.
This is not to say that one way of presenting the information to the audience is better than the other way, only that the differences between the art forms are clearly demonstrated in the comparison of Shakespeare's original play with the Romeo + Juliet movie version.