Selanne scored twice in the second period (once on a penalty shot) and again in the third en route to a five-point night for the Ducks, who rebounded from an early 2-0 deficit and swept the season's series from Colorado.
Cam Fowler added a goal and an assist, Jason Blake tallied and Saku Koivu added a pair of assists as the Ducks retained their hold on the seventh seed in the Western Conference playoff standings with six games remaining.
Ray Emery turned aside 31-of-35 shots to earn the victory.
Matt Duchene notched a goal and an assist, Milan Hejduk collected three helpers and Brian Elliott made 37 saves for the Avalanche.
Boston schools pull out free condoms over wrapping complaints
Ray Liotta sues skin care company over use of likeness