60 Minutes rewind. For many of us, Rob Reiner will forever be Meathead, the liberal foil to Archie Bunker in CBS's All in the Family. But it's as a director that he's really made his mark with some of the most memorable movies ever.When Harry Met Sally, Stand by Me, A Few Good Men, and The Princess Bride. But Reiner's first film almost didn't get made. All he had for This is Spinal Tap about a failing madeup British rock band was a fourpage outline.No script because the movie was totally improvised. Release ...