Philadelphia opened the season by dropping its first six games. Then, after winning four straight, the Flyers lost another three in a row.
"We dug ourselves a little bit of a hole so it's nice to climb up in the standings," Knuble said.
Simon Gagne set up the go-ahead goal by stealing the puck at the blue line and passing it to Mike Richards, who fed Knuble in the slot for a one-timer.
Philadelphia coach John Stevens said Knuble has "really played well" since he was put back on the top line with Gagne.
"I think he looks reborn," Stevens said about the 36-year-old veteran. "Those two have chemistry together. Mike keeps himself in good shape. He works hard at his game. He is out long after practice."
Scottie Upshall and Jeff Carter also scored for the Flyers. Gagne extended his points streak to eight games (three goals, 10 assists) with a pair of assists on Knuble's goals.
Mike Modano scored twice and Landon Wilson had a goal for the Stars, who have lost three straight and six of seven.
Modano pulled within two points of 1,300. Now in his 19th season, he would become the 31st NHL player to surpass that plateau.
"A couple of bang-bang plays, a couple of pucks lying around and I took advantage of them," Modano said.
Martin Biron, who stopped 22 shots, said Philadelphia's penalty killing played a huge role in the win. The Flyers held the Stars scoreless on all five power plays, including three in the last 12 minutes.
"That's two games now that we got a kill in the last minutes of the game," Biron explained. "I don't think they got a shot in the last minute today. A lot of blocked shots, screen plays that we are cutting, or we're keeping the play to one side of the ice. It makes it a lot easier for the guys to make their reads and make it easier for me."
Dallas goalie Marty Turco, playing in his 400th game, had 21 saves.
The Flyers took the lead at 3:15 of the first period when Upshall took a pass on the stick from Joffrey Lupul and shoveled the puck into the net while sliding on one knee.
Wilson tied it at 11:33 with a wrist shot past Biron's glove side. It was his first goal since March 2004 with Pittsburgh.
Knuble put the Flyers ahead 2-1 at 16:00 when he muscled between Dallas defenders Mike Ribeiro and Trevor Daley and scored with a forehand shot.
Dallas made it 2-all when Modano ripped a rebound of a shot by Loui Eriksson into the net at 2:30 of the second period.
Carter and Modano traded one-timers off passes from behind the net to leave the score tied at 3 after two periods.
Carter scored at 14:22 after taking a pass from Scott Hartnell. Modano got his second goal of the night at 17:26, with Daley getting the assist.
Carter tied Buffalo's Thomas Vanek for the NHL lead with 15 goals.
Dallas coach Dave Tippett said a slow start hurt the Stars, who fought back from deficits of 1-0, 2-1 and 3-2.
"We didn't start very well at all," Tippett explained. "We had a lot of deer in headlights. Once we got engaged we were OK."
Philadelphia's Andreas Nodl had an apparent goal disallowed in the first period when the referee ruled the puck was frozen under the goalie.
Notes: Dallas C Steve Ott sat out with a broken hand. ... D Matt Niskanen was a healthy scratch. ... Wilson played in his 350th game. ... Hartnell and D Kimmo Timonen played in their 100th games for the Flyers.
