Denoting the singular protagonist of W.W. Jacobs' "The Monkey's Paw" can be challenging. Some readers may identify Mr. White as the protagonist, and others may identify the pair (both Mr. and Mrs. White) as the protagonists. Depending upon the specific identification of the protagonist, the answers to the question posed changes.
If one identifies Mr. White as the protagonist, the central conflict he faces is giving in to his wife's request to wish for the return of their deceased son. Mr. White worries that the passing of 10 days and the fact that their son's body was mangled may not prove his return to be promising. Yet, he gives in to his wife and makes the wish. Later, as knocking on the door begins, Mr. White wishes away his son. Internally, Mr. White knows that wishing for his son's return may not be a good thing, yet the love he possesses for his wife persuades him to give in to her wishes.
If one identifies the pair as the protagonist, using the talisman (the Monkey's paw) in the first place sets itself up as the main conflict. Both Mr. and Mrs. White are unsure about making any wishes. The warning provided by the sergeant proves to worry them enough.
Regardless of defining the protagonist, conflict truly exists within the story. Mrs. White desires her son's return so much that she is willing to face whatever horrors his return brings. On the other hand, Mr. White knows that the son's return cannot be what is best. He goes against his wife's desires and wishes their son away at the last moment.