The France international's penalty and Aaron Ramsey's breakaway goal gave the Gunners a comfortable 2-0 win at rock bottom Aston Villa on Sunday
They moved a point clear at the top, although Leicester will replace them if they beat Chelsea at the King Power Stadium on Monday
Giroud scored a hat-trick in Wednesday's 3-0 Champions League win at Olympiacos and netted his 50th league goal for the Gunners - and 14th of the season - at Villa Park and boss Wenger reckons the 29-year-old can be under appreciated.
He said: "I believe he is at the top of his game
He is questioned sometimes but finally the numbers get people to realise he is a good player.
"Olivier has improved technically
His link play is better and when you have the option to go for long balls he is always an interesting option
"He's not got electric pace, he is more a player who likes to play with his back to goal
He is not spectacular individually but he is a very efficient player for the team
Mentally he is very strong."
Arsenal face second placed Manchester City next Monday with the chance to be top at Christmas after Petr Cech also equalled David James' clean sheet record with his 169th shut out in the Premier League at Villa Park
And Wenger is grateful for the long break to prepare for the game against a title rival
He said: "Let's see tomorrow, if Leicester beat Chelsea they have a very good chance to be top at Christmas.
"It's a big game, we want to win at home and beat City at home
We have eight days to prepare
It will be an interesting one but we at least can recover first and prepare then
"I was a bit anxious today because we had given a lot on Wednesday and came back very late on Thursday morning
I knew Villa were fighting to survive."
Alexis Sanchez is still missing with a hamstring injury but Wenger refused to completely rule him out of the game against City
"I think the closest to have the chance is Sanchez but medically we think he won't be ready - but Sanchez being Sanchez you never know," he added.
In contrast to Arsenal, Villa are eight points from safety after 15 winless games in the league having won just two points from the last 30 available
They go to Newcastle on Saturday before facing fellow strugglers Norwich and Sunderland over Christmas and boss Remi Garde, who won the title with Arsenal in 1998, admitted the games will define the season
"Probably, we will have to win if we want to be safe," said Garde, who recalled Jack Grealish to the squad after dropping him for two games for partying after a 4-0 defeat to Everton last month
"We can still be safe but we are coming into a period where we have to win
I see this situation as more of an opportunity than a problem but we have to be ready
"I still believe we are capable of winning the next game
I enjoy working in this league
We are struggling, I still haven't won a game and I'm very frustrated but I know in football you can change things with work."
Source : PA