Pascal Dupuis, Chris Kunitz, Ruslan Fedotenko and Matt Cooke scored for the Penguins.
Scoring more than three goals for the first time in 10 games, the Stanley Cup champions ended a three-game losing streak and clinched a berth in the Eastern Conference playoffs for the fourth consecutive season.
The Flyers generated little offense and lost their fifth in a row and seventh in eight games.
At Glendale, Arizona, the Phoenix Coyotes, the surprise team of the NHL, celebrated their first playoff berth since 2002 with a big win over Colorado Avalanche.
The Coyotes, still owned by the league after going through protracted bankruptcy proceedings last summer, clinched the postseason spot earlier in the day when Calgary lost to Boston.
Four of Phoenix's goals came from players who joined the team at the March 3 trade deadline - Lee Stempniak, Wojtek Wolski and Derek Morris.
Stempniak, with both scores in the third period, has 12 goals in 12 games since he arrived from Toronto, including four two-goal games.
At Nashville, Niklas Kronwall, in his first career shootout try, scored the winning goal in the 11th round to give Detroit a win.
Jimmy Howard stopped nine of Nashville's 10 shootout attempts to make Kronwall's goal stand up as the winner.
Detroit has won five straight and eight of nine to move into a more solid playoff position. The Red Wings jumped out of eighth place in the tightly packed Western Conference race.
Nashville lost for just the second time in nine games. The fifth-place Predators are only one point ahead of the surging Red Wings.
At San Jose, Patrick Marleau had a goal and two assists for the Sharks, who stretched their winning streak to three.
Marleau's 42nd goal gave the Sharks a 2-1 lead with 10:31 left in the second. Joe Pavelski scored two minutes later, and Ryan Clowe added an empty-netter with 11 seconds left to make it 4-2. Dany Heatley also scored for San Jose.
The Sharks have bounced back from a five-game losing streak that dropped them out of first place in the Pacific Division.
Vancouver's Henrik Sedin, the NHL scoring leader, had two assists to push his point total to 101.
At Los Angeles, Brad Richards scored two power-play goals less than 5 minutes apart in the second period, Brenden Morrow and Steve Ott also connected during man-advantages, and Dallas avoided a six-game sweep by Los Angeles.
Mike Ribeiro and Stephane Robidas each had two assists, and Kari Lehtonen made 29 saves in his sixth start with Dallas since being acquired from Atlanta.
At Boston, Dennis Seidenberg, David Krejci and Zdeno Chara scored power-play goals, and Tim Thomas stopped 31 shots for the Bruins in his first shutout since Dec. 21.
Patrice Bergeron and Mark Recchi also scored for the Bruins, who won for just the third time in 15 home games and moved into a share of seventh in the East with Philadelphia.
At Montreal, Patrik Elias and Jamie Langenbrunner had power-play goals and Dainius Zubrus also scored for New Jersey, which clinched its 13th straight playoff berth with a win over Montreal.
Martin Brodeur made 25 saves for his 41st victory of the season and New Jersey's 44th.
Brian Rolston recorded his 700th career point when he scored into an empty net at 19:50.
The Devils, who have won four straight in Montreal, moved into a share of first place with Pittsburgh in the Atlantic Division with 93 points. New Jersey, which snapped a four-game losing streak on the road, holds the edge for second place overall in the Eastern Conference with one more win than the Penguins.
At Buffalo, Patrick Lalime won his 200th career game as Buffalo clinched its first playoff berth in three years with a rout of Tampa Bay.
Lalime, who made 22 saves, is the 66th NHL goalie to reach the milestone.
Derek Roy posted his fourth career hat trick and added an assist for Buffalo, which hadn't reached the playoffs since the 2007-08 season.
Paul Gaustad, Jochen Hecht, Jason Pominville, and Adam Mair also scored for the Sabres, who have won five of six.
At Toronto, Nikolai Kulemin scored 39 seconds into overtime and Jonas Gustavsson made 36 saves to outduel Swedish counterpart Henrik Lundqvist in Toronto's comeback victory over New York.
Gustavsson extended his winning streak to seven games, the longest run by a Maple Leafs goalie since Ed Belfour won seven straight from Nov. 22-Dec. 6, 2003.
At Raleigh, Rich Peverley and Evgeny Artyukhin scored 57 seconds apart in the second period to help Atlanta beat Carolina.
Niclas Bergfors added a goal late in the second for the Thrashers, who snapped a two-game skid to stay in the thick of the Eastern Conference playoff race. Johan Hedberg finished with 34 saves and earned his second shutout of the season.
At Ottawa, Daniel Alfredsson scored the winning goal early in the third period and Brian Elliott made 20 saves for Ottawa, which topped Florida for its fourth straight victory.
Matt Cullen and Peter Regin also scored for the Senators.
Erik Karlsson assisted on all of Ottawa's goals.
Stephen Weiss and Steven Reinprecht scored for the Panthers. Tomas Vokoun finished with 22 saves.
At Columbus, Josh Bailey scored 2:58 into overtime to send the New York Islanders to a come-from-behind win over the hosts.
Kyle Okposo, Sean Bergenheim and Jon Sim scored in regulation for New York, which won for the first time at Nationwide Arena in its sixth attempt. It was the only NHL arena in which the Islanders hadn't won.
The Islanders earned their second road victory since Jan.
18 despite squandering a two-goal lead.
