Basically, the main character of a story, the person you want to succeed, is the "protagonist." The "antagonist" is the character that opposes the protagonist.
Claudius was hamlets Uncle and later became his stepfather because his mother Queen Gertrude married Hamlets uncle "Claudius".
The Character Silas in the poem, "The Death of a Hired Man," is and elder man whom tries to redem his job again at the home of an old employer. He is the somewhat anatgonist of the story since he is the one that causes the comotion and the conflict in the poem.