[Because there is only one question permitted at a time, and since the first question has already been answered, your question has been edited to the latter one.]
In such a compact short story as that of Kate Chopin, every element contributes to the meaning; therefore, the title signifies much. In fact, it is a metaphor for the sequence of events of Chopin's narrative. For, what occurs to Louise Mallard in one hour's time is a story of itself. In the exposition, for instance, Mrs. Mallard receives the supposedly tragic news that her husband has been a victim of a train wreck. However, within a few minutes the reader perceives that it is Mrs. Mallard who has been victimized much more than the "late" Bentley Mallard. As she "would have no one follow," Mrs. Mallard closes the door to her bedroom and collapses into her armchair which faces an open window. Looking at the burgeoning Spring outside, Louise Mallard, an individual who has been repressed, is now "free!" and her independent spirit emerges like the new buds on the trees. With the realization that she is no longer the property of her Victorian husband, Louise contemplates all that she will be able to do. With feelings of being "a goddess of Victory," Louise emerges from her room within an hour and stands at the top of her stairs ready to descend as a liberated woman. However, when her husband miraculously appears, Louise Mallard's heart stops with the shock, and it is Louise who falls down the stairs, killed from having the joy of freedom--"the joy that kills"--repressed yet again. The life of Louise Mallard, not Mrs. Mallard, has been "the story of an hour"; for only sixty minutes Louise Mallard has been freed of "a heart trouble" as described in the story's beginning and at the conclusion. Indeed, the title contributes great significance to Kate Chopin's momentous story.