Led by Huet, who recorded his third straight win, the Canadiens' defense frustrated a potent Atlanta lineup featuring three of the NHL's seven top scorers -- Marian Hossa, Ilya Kovalchuk and Vyacheslav Kozlov.
"They tried to throw a lot on net and they didn't have many second chances -- if they had one," Huet said.
Ryder scored his first goal in 10 games, netting a power-play tally in the first period. Perezhogin restored Montreal's one-goal lead in the third with his first in nine games.
"Sometimes you go through slumps but I try not to get frustrated," Ryder said. "I just make sure I keep shooting, and it went in tonight."
Radek Bonk scored into an empty net with 1:14 remaining.
Johan Hedberg stopped 30 shots for Atlanta, which extended its season-high losing streak to four games in the wake of its second four-game winning streak.
Montreal, which lost 5-1 in Florida on Thursday to split a four-game trip, hasn't lost consecutive games this season.
"Atlanta has a lot of firepower," Ryder said. "They have guys that can score any time in the game and we knew that they were going to keep putting it at the net, and Huet always kept coming up with the big save and held the fort for us."
Savard's No. 18 was retired by the Canadiens in a 40-minute pregame ceremony.
"When you accomplish what Serge did, on the ice and off the ice, it was well worth it," said Thrashers coach Bob Hartley, whose team lost 5-3 to Dallas on Friday. "It was an honor for us to play in tonight's game and to see the banner up high in the rafters."
The Hall of Fame defenseman won eight Stanley Cup rings while playing for Montreal from 1966-81, and two more -- in 1986 and 1993 -- as the team's general manager.
"You get a little adrenaline rush when you see his banner going up and how excited he was," Ryder said. "It was great seeing that and I think it actually gave a little boost to some of the guys and maybe motivated them to play a little better."
Ryder opened the scoring on a power play 14:18 in with his first goal since Oct. 26. He jumped on Hedberg's rebound off Souray's point shot and drove a slap shot over the Atlanta goalie's left shoulder from the left circle for his fifth goal.
"It kind of popped out perfect for me," Ryder said. "I just walked into it and let it go."
Huet had no chance on the tying goal 3:30 into the third. Metropolit's wild shot from the left side struck Souray, who was standing in front of the goal mouth. The puck deflected off the Canadiens defenseman and past Huet into an open right side.
The Canadiens goalie drew cheers from the sold-out crowd moments later when he stopped Kozlov's backhand.
Perezhogin restored Montreal's one-goal lead shortly after when he stripped the puck from defenseman Andy Sutton and drove the net. He beat Hedberg for his second goal, his first since Oct. 28.
"That was a really tough play," Hartley said. "Whenever it bounces in front of a defenseman and their guy is coming in at full speed and it's laying right there, it's a tough way to lose a game. I can't fault one of my guys for tonight's game."
Scotty Bowman was given a large ovation when he was introduced to speak before Savard. "I don't ever remember Serge leaving his partner caught in disarray," said Bowman, Savard's coach for five Stanley Cup wins with Montreal. ... Canadiens LW Guillaume Latendresse assisted on Ryder's goal. The 19-year-old rookie has three goals and two assists in five games since joining Montreal's top line after being held without a point through 13 games.