David, your synopsis is actually pretty good.
Talon, the crux of the story is that King Ahasuerus ruled over all the civilized world, so destroying all the Jews in his kingdoms would have amounted to 100% genocide. We celebrate the overturning of Haman's plot, where oppression and fear were turned into rejoicing, by giving to charity, feasting, and sharing gifts with friends.
We traditionally drink enough to get so tiddly we "don't know Haman from Mordechai" when we hear their names. It's the men who do this - we ladies refrain usually. Another way to do it is simply to take a nap, and guys like my husband, who don't drink a drop, ever, do that instead.
Miriam