Point 1 - right
Point 2 - right
Point 3 - wrong, wrong, wrong
Why do you think people get so up in arms over Supreme Court openings and nominations? They do indeed have the last call on interpreting and applying the Constitution and, in fact, all American law. The Congress tries to override their decisions from time to time, but if the decision is based on Constitutional law rather than merely common law or precedent, the Supreme Court wins. It is serious stuff, so when you vote for President you should be voting for the person you want to have in charge of nominating these justices rather than the lesser of two evils or the guy who helps you assuage your guilty feelings (I won't go further down that particular thought path further, because that would definitely open up the controversy).