It depends on whether you mean the coach with the most wins (longevity stat) or the coach with the highest percentage of wins in his career. Paterno is the leader among active coaches in number of wins. Although technically he is no longer active as of end of 2011.
Highest win percentage will depend on how many seasons you set as the minimum for the stat. Obviously a coach could be 100% after 1 season, so it makes sense to set a bar of at least 5 or 10 seasons.
Bob Ford. University at Albany. Division 1-AA FCS
Knute Rockne with a record of 105 wins, 12 losses and 5 ties
Coach George Curry from Berwick is the winningest coach in PA history.
Bob stoops
Kenneth McKinney
jim drewery
NFL: Don Shula.
George Curry - Berwick
Which coach became the winningest coach in NFL history while with the Dolphins
1993 Don Shula Professional football Winningest NFL coach
Dan Reeves is the winningest coach in Atlanta Falcon history with 49 wins.
I Stand to be corrected ,but as far as I can determine, the Caps' winningest coach is Bryan Murrray with 363 wins.