In "The Crucible" Danforth believes it is a "sharp time" where good and evil are not "mixed" in people, but are easily distinguishable. Do you agree?

I disagree.  Danforth's assertion is one that he sticks to, because it emphasizes his skills as a judge, and what he has been doing there.  And, he states it right after Proctor, Giles and Francis have come in and tried to assign ulterior motives to many of the townsfolk for their accusations.  If those men were right, that would mean that his judgment of witchcraft were wrong.  So, he is trying to reassert his authority and power there.

He is basically saying that we live in a time where people aren't really evil--but when they are, they are SUPER evil and do things like become witches.  And when they do that, it's easy to discern, easy to root out.  Well, if you look at the evidence from the play, that is not true at all.  Jealousy, greed, bitterness, attraction, desire--these are all emotions that all of experience, regularly.  They are negative, often destructive feelings, but the average person feels them quire regularly.  They aren't SUPER evil, they are human.  And they exist in all sorts of subtle, complicated ways that sometimes we don't even realize ourselves.  We don't even know what we are feeling half the time, we just know we're in a bad mood that day.  So, evil is not clear-cut, it's not dramatically huge, and it doesn't only occur in rare cases of witchcraft.  In the case of Salem, the accusations of witchcraft occurred NOT because these ladies and men were witches, but because the accusers all held complicated labyrinths of normal, negative human emotions in their hearts.  They were jealous, afraid, bitter, and greedy.  They weren't witches, they were human, and that happens all of the time, and it's complicated and tricky to figure it all out, not easy.

Those are just my thoughts on the matter, but I hope that they helped to spark your own.  Good luck!