A couple of other examples in the very first scene of the film:
1. Bonasera's daughter was gang raped and badly beaten to the point of disfigurement. The perpetrators were found guilty in a court of law, but because of who they were (good old white boys) and his daughter's immigrant background, the judge suspended the sentence.
As Bonasera says: "They walked free that very day!"
The film depicts a lawful but inadequate justice system, appealing to the audience's pathos. When a court of law is corrupt and incapable of carrying out justice, who should you turn to? You turn to Don Corleone. He may act outside the law, but he's better than the law. The law did not supply justice, but Don Vito will give you justice.
2. In this light, Bonasera asks Don Corleone to kill the guys who raped and disfigured his daughter. But Don Corleone does not acquiesce -- he tells Bonasera that his daughter is still alive, so killing them would not be equal justice. Instead, the writers (through Don Corleone's dialogue) make an appeal to the audience's logos ... equal justice would be an eye for an eye. Since Bonasera's daughter is now disfigured, Don Corleone will see to it that these boys will be permanently disfigured too... but they will live.
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So as you can see, right from the very first scene the characters are portrayed in a positive light. The film does not go overboard though and act like these guys are saints ... to do so would discredit the storyteller. Instead the counterpoint is presented in muted fashion. We don't ever see Don Corleone and Luca Brasi hold a gun to the poor band leader's head, we hear about it second-hand from Michael. We don't see anyone break into Jack Woltz's mansion and put a severed horse head in his bed, it just ... happens (and Woltz is presented as a pedophile too). What this does is it presents all sides of the story in an honest way, but it emphasizes the good parts of the main characters and minimizes the bad parts. That is effective storytelling.
When Don Corleone gets shot and incapacitated for most of the rest of the film, his son Michael becomes the new center of attention. He was already presented as a war hero and good guy. Now he's just trying to look after his father, like anyone else would do. He shoots two men dead in cold blood right in the middle of the film, but they were the bad guys. Everyone he kills or has killed in the film was a bad guy.
Just some things to consider.
