Grant Holt levelled matters via the penalty spot after the 26-year-old broke the deadlock early in the second half, only for Agbonlahor to claw back the three points with an 89th-minute winner.
The victoryy aw Villa rise to 13th in the table with two games remaining - though 18th-placed Wigan have a game in hand against Swansea on Tuesday - and Lambert lavished praise upon his matchwinner after the huge boost to his team's survival hopes.
"The goals from Gabby [Agbonlahor] were top-class. Gabby has been playing ever so well. He's an absolute threat. He has speed and power. He is playing excellently for us," he told reporters.
"He's got the speed to hurt teams. Today I thought his goals were fantastic. As I said, he has incredible speed. He's one of the quickest lads I have ever seen. But allied to that, he has the power.
"And his goals? To break the Dwight's record is a terrific achievement. He's playing really, really well at this moment in time. If he can keep doing that and we keep building, it will be great."
Lambert also reserved praise for the rest of the team and, in particular, the provider of the pass for the decisive goal, Ashley Westwood.
"I thought the pass from Ashley for the second one was outstanding. The ball was an absolute peach," he continued.
"Overall, it was a big, big performance because of the effort we put. I thought it was a bigger effort than Monday."