The hosts came into Saturday's game having taken just one point from their previous six matches, but Ashley Westwood's early strike and two goals from Andreas Weimann sparked celebrations among the Villa faithful.
Paul Lambert's men are now six points clear of 18th-placed Norwich City and, with only two games remaining as well as a vastly superior goal difference, are effectively assured of enjoying top-flight status for a 27th consecutive campaign.
After Westwood's first-minute opener, Hull replied shortly before the half-hour mark when substitute Jordan Bowery put through his own net.
Weimann took centre stage in the closing stages of the opening half, twice heading in as the hosts secured a first home win since March 15.
The defeat leaves FA Cup finalists Hull still without a win since booking their place at Wembley and looking over their shoulders at the bottom three, although they too will be safe if Norwich fail to win at Chelsea on Sunday.
Villa made a blistering start, taking the lead inside 60 seconds through Westwood's composed finish.
Gabriel Agbonlahor played an influential role, breaking free down the left and - after what looked like a push on Curtis Davies - cut the ball back for Marc Albrighton, who poked a pass into the path of Westwood and the midfielder took a touch before planting a shot beyond Steve Harper.
Agbonlahor departed the action midway through the half after picking up a knock, and his replacement Bowery unwittingly brought Hull level in the 28th minute.
Tom Huddlestone slid a disguised free-kick into the path of Liam Rosenior and, although the full-back appeared to be in an offside position, play was allowed to continue and his low cross was turned into the net as Bowery got his feet in a tangle.
Huddlestone brought a flying save out of Brad Guzan six minutes later but Harper had to rush from his line to deny Weimann and then tip Bowery's header over the crossbar at the other end as the game opened up.
Weimann was not to be denied for long, however, nodding in from close range after Nathan Baker was denied by the bar in the 41st minute.
Villa Park was jubilant as the Austrian was on target again in first-half stoppage time, glancing in Bowery's left-wing delivery from 10 yards.
In a second half that offered little in comparison to the first, Bowery tested Harper with a rising drive on the hour, while Guzan got down low to his left to comfortably hold Huddlestone's effort from the edge of the box 15 minutes from time.
Hull were unable to force a way back into proceedings as the game petered out, with Villa now finally able to plan for life in the Premier League next season.
