The striker scored twice before half-time to cancel out Ashley Westwood's opener before the January signing scored his first goal for the team and Chicharito added a late fourth
Much of the game's build-up had been dominated by a planned protest against David Moyes' management of the struggling champions, with a plane trailing the message 'Wrong One - Moyes Out' flown above Old Trafford during the contest.
A midweek defeat to local rivals Manchester City was the latest of United's setbacks in a tough season, tipping some fans over the edge.
|VIEW FROM OLD TRAFFORD
|By Peter Staunton
All over at Old Trafford and for the first time in more than a year, Manchester United score four in the league in front of their own fans.
It's a rare and undeniably bright day for David Moyes and his squad.
Aside from going 1-0 down, they had things their own way. Two goals for Wayne Rooney, a confidence-bolstering first for the club for Juan Mata and a late Chicharito effort put the gloss on this United win.
Bayern loom on the horizon but United can face the German champions in reasonable confidence.
However, Wayne Rooney - so often the bright light in United's faltering campaign - dragged the hosts in front with a double before half-time, taking his tally to six goals from his last six league games.
Any home jitters were put to rest 12 minutes into the second half as Juan Mata scored his first United goal, with the home fans responding with rousing renditions of pro-Moyes chants, before substitute Chicarito rounded matters off late on with a typical poacher's finish after good work from Adnan Januzaj.
The win keeps United within reach of the top six and also serves as a perfect tonic ahead of Tuesday's Champions League quarter-final first leg against holders Bayern Munich.
Moyes was warmly applauded onto the pitch by the Old Trafford faithful, as those inside the stadium aired their backing of the manager, and the planned fly-over passed with little incident two minutes into the game.
However, the home fans' patience was put under strain 12 minutes in as Westwood curled a superb free kick home and past David de Gea's despairing dive.
Villa kept the pressure on as Ciaran Clark sent a free header over the crossbar.
But United equalised on the counter-attack, a totally unmarked Rooney nodding Kagawa's cross past Brad Guzan.
That goal kicked United into gear, and they went ahead just before the interval as Leandro Bacuna's clumsy lunge on Mata resulted in a penalty that Rooney lashed past Guzan.
Christian Benteke wasted two big chances to equalise for Villa in the opening minutes of the second half and those misses came back to haunt the Belgian as Mata gave United breathing space.
Marouane Fellaini's presence in the penalty area played havoc for the Villa defence, and Mata stole in to open his United account with a low right-footed effort.
Rooney went close to a hat-trick, working space with a sensational first touch from a long ball only for Guzan to deny him, with the striker withdrawn soon after as Moyes turned focus to Tuesday's clash with Bayern.
Chicharito then got on the end of Januzaj's excellent cross in stoppage time to seal the impressive win and give Moyes renewed vigour ahead of arguably his toughest test since taking over from Sir Alex Ferguson.