No, Russell Westbrook has not yet won a championship. The closest he has come to a champion was in 2012, when he and the Oklahoma City Thunder reached the finals and lost 4-2 to the LeBron James and the Miami Heat.
People argue that it's either Russell Westbrook, James Harden, Lebron James, or Kawhi Leonard. Personally (stat wise), I think Westbrook is the best player this year.
thunder it's Russell Westbrook, James Harden, and Kevin Durant
Go lebron James
LeBron James will always be better then Steve Nash.