Substitute Chopra's 83rd minute goal took Roy Keane's side a further step away from the threat of relegation.
It was also Sunderland's first goal in 456 minutes play and their first success in the league at Villa Park since 1982.
Poor Aston Villa slumped to their second successive defeat and have now picked up only two points from the last four games to seemingly indicate that they have shot their bolt.
Any thoughts of European football manager Martin O'Neill may have had have disappeared as a result of this very disappointing home performance.
They could have no complaints about this latest setback as Sunderland more than deserved their belated success.
The Black Cats played with a great deal more purpose than Villa on the day with Andy Reid a driving force in midfield with some astute passes.
Although without the services of their talented striker Kenwyne Jones, the North-East side posed plenty of problems for Villa who faded badly after a bright start.
It was in this period that Shaun Maloney was a big threat and he provided the cross from which John Carew produced an overhead kick which went just wide of the post, Villa's only real goalscoring chance.
Sunderland were always lively with Daryl Murphy providing some smart play with his fellow Irishman, Roy O'Donovan, who gave Martin Laursen and Zat Knight a hectic first half.
Villa themselves counted themselves rather fortunate in the opening period when referee Howard Webb certainly favoured the home side with a couple of suspect decisions.
Scott Carson, who had another miserable game, handled outside the area, while Nigel Reo-Cocker handled the ball in the penalty area straight in front of Webb.
Villa conspired to make like difficult for themselves. Ashley Young was off the pace while Gabriel Agbonlahor never appeared capable of ending his recent barren goal spell.
Sunderland central defender, Jonny Evans, superbly supported by Nyron Nosworthy, was outstanding and deservedly took the man of the match award.
But it was Chopra who popped up to boost Sunderland in the 83rd minute. He had taken over from O'Donovan and was not particularly a danger man.
But a long punt down route one by Kieran Richardson found Chopra, who coolly lofted the ball over the head of a far from confident Carson for the matchwinner to the utter dismay of Villa.