Scott Parker's strike settled a roller-coaster clash at Upton Park and allowed the Hammers to take a giant stride towards Barclays Premier League safety.
"It was a great finish and not an easy shot because he did not have an angle, but he hit it perfectly and it was a great goal and great result," said Zola.
"I cannot celebrate yet. We want to stay focused and want to finish this championship with some more points."
He added: "I understand the fans were nervous like us and the way we started the game did not help, but they have been behind us and while we have not given them much satisfaction they have always been behind us and I'm grateful for that.
"[The players' reaction to the goal] was very gratifying. It shows that despite all the problems, there has been a compactness between players and staff.
"There has been a lot of stick but we have been together and that is the result, that was the meaning of the celebration."
It was a key moment as West Ham raced into the lead with goals from Ilan and Radoslav Kovac. Hugo Rodallega drew Wigan level again before Parker stepped up to seal the victory.
"The save was the key moment. Going two down against Wigan would have been tough, but the reaction was amazing and we never let ourselves down," said Zola.