Berbatov gave United the lead from Nani's delivery before Park Ji-Sung combined with Wayne Rooney for 2-0.
Berbatov pounced on a Pascal Chimbonda backpass to score the third before grabbing his hat-trick with a firm strike from just inside the area.
Nani lashed in to make it 5-0, Berbatov followed up Park's blocked shot and then fired in an angled strike before Chris Samba's late consolation header.
United's Bulgarian ace became the fourth player to score five goals in a Premier League game, joining former United striker Andy Cole, Newcastle's Alan Shearer and Tottenham's Jermain Defoe.
But both Wayne Rooney and Nani had a huge hand in helping Berbatov achieve his feat during a victory that United fans will savour for a while, not only because it took them to the top of the league but because of the manner of the performance.

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Despite going into the match unbeaten in their last 28 matches, their displays during the last few weeks have been too reliant on their battling qualities rather than the fluency fans are used to.
Part of the reason had been Berbatov's form - after scoring seven goals in his first six games he had gone 10 matches without adding to his tally. Rooney's lack of form following his injuries and U-turn on seeking a move had hardly helped.
Against Blackburn the telepathy between the pair was back, as was their touch.
The pair combined as early in the second minute for the opener when Nani's free-kick was met with the faintest headed flick from Rooney and Berbatov stuck out his leg to finish from six yards.
Blackburn keeper Paul Robinson, who was injured in a collision with Anderson in the lead up to the goal, did well to claw away United's next effort when he denied Patrice Evra from Nani's corner.
But even if there were two Robinsons in goal, Rovers could not have stopped United's second.
It was Nani again who started the move as he fed Park. The South Korean played a one-two with Rooney on the edge of the area before running on and poking his shot past Robinson.
if that was sublime, the third was stupid - on the part of Rovers.
Chimbonda, 40 yards from his goal on the left touchline and under little pressure, played a terrible backpass to Robinson which was intercepted by Berbatov, who smashed the mistake past the Rovers number one.
It was 3-0 at half-time, and any hopes Sam Allardyce's Rovers had of United easing off the accelerator were shattered two minutes after the break.
Nani sped down the right then cut inside and laid the ball back to Berbatov, who began the move he started inside his own half with an effort high into Robinson's net.
A minute later Nani got his personal reward when he cut inside Chimbonda to place his effort past Robinson.
A sixth arrived as Rafael da Silva raced into the 18-yard box before playing in Park, whose attempt was blocked by Samba only for Berbatov to smash in.
And with 20 minutes left to play, Berbatov joined an elite list by sliding in his fifth from an angle after his attempt to square the ball to Rooney at the far post was thwarted.
Blackburn's only effort on target resulted in a goal when Samba nodded in substitute Josh Morris's cross eight minutes from time.