How are Romeo from Romeo and Juliet and Tony from West Side Story alike and different?
Since West Side Story is based off Romeo and Juliet, the plots of both stories have much in common, as do their main characters. Still, West Side Story is an adaptation meant to show the story in a new light, so certain things about Romeo were changed when he was rewritten as Tony.
First, the two characters occupy different positions in their social worlds. Romeo's family, the Montagues, are very wealthy and have a lot of social power in Verona. Tony, as the child of poor Polish immigrants, does not.
A social similarity they both have is their recent absence from their usual social life. Tony has been missing from the gang life of the Jets for a month, while Romeo has been moping around, too love-sick for Rosaline to engage with his friends and family. On a related note, both seem sick of the constant fighting that defines their world. Romeo seems always more of a lover than a fighter, rejecting Tybalt's taunts and attempt to engage him in a sword fight after Romeo secretly marries Juliet (making Tybalt his kin). Tony also seems sick of fighting, having given up his role as leader of the gang and seeking to distance himself from gang life.
The differences here are more subtle. While Romeo is pulled away from the conflict by his all-consuming infatuations (first with Rosaline, then Juliet), Tony makes a more active decision to renounce gang life and fighting. Romeo's refusal to fight Tybalt seems more a passive response to Juliet's assumed wishes than the moral stand that Tony is trying to make. This is one example of how Tony seems more mature and thoughtful than the rash Romeo.
Another moment for similarities and differences is at the meeting of their true love. In both stories, the moment of meeting is "love at first sight," where the beloved stands out from the crowd and Romeo and Tony engage in a romantic moment (sonnet and kiss for the former, dance for the latter). A difference lies in their reactions upon discovering the girls' backgrounds. Romeo is immediately concerned that Juliet is a Capulet, but Tony seems more blasé about it, saying Maria's father will like him.
As many of these plot-based decisions suggest, Romeo is more of an unrealistic dreamer than Tony is, much more inclined to mope in self-pity over a girl. Tony seems more self-assured than Romeo, especially in taking a moral stand over the fighting and trying to stay out of gang life and move on. While Romeo sees the family feud as inevitable and impossible to circumvent, Tony believes that he can break up the rumble and leave gang life behind.