Coach K would not ever leave Duke he's the man and will stay the man there until he doesn't want to coach anymore. This makes me sad because I'm a Tarheel fan and he's a royal pain in the ass.
Rick Pitino has already tried and is much better suited as a college coach.
Tubby Smith would be a great NBA coach and might very well be on his way out at Kentucky. I'd be more than pleased to give him a shot as our coach.
Lute Olson? I don't really know enough about him to make a good evaluation of him as an NBA coach.
Bobby Knight, He'd never even consider it and nobody would play for him either. The first time he got up in somebody's grill and started screaming at him he'd get slapped up side his head. At his age that wouldn't be good.
Roy Williams would not leave Carolina ever, he had a hard enough time leaving Kansas. He's the most loyal individual I've ever met.
Jim Calhoun, Once again I don't know enough about his situation to make a good evaluation.
All of these coaches are without a doubt some of the best coaches to ever coach in college. Knight just passed Dean Smith as the all time winningist coach in history. Before Roy or coach K retire they will both top his numbers.
On a side note I saw a comparison as to the players that Dean coached as to the ones Bobby Knight Coached. Dean has 12 players that are now in the NBA hall of fame. Knight has 1. The announcer said this meant he had done it with lesser talent. I don't think so, I just think that UNC has always played more of an NBA style or up tempo game than Indiana. Knight's one great NBA player is Thomas.