The Argentine superstar only played 30 minutes of football, but added a double to goals from Adriano and Villa as Luis Garcia's men were brushed aside with little resistance
The Catalan giants laboured during the early stages of the match but took a single-goal lead into the break through Adriano. Second-half substitute Lionel Messi then netted twice before a Javier Mascherano own goal robbed the visitors of a clean sheet, but David Villa rounded off the win.
A number of injuries meant that Barcelona's attack had an almost second-string look to it, with Pedro, Cesc Fabregas and Cristian Tello leading the line while Messi and Villa, who were lacking in fitness, started on the bench.
The Blaugrana controlled possession throughout the first half but did not use the wings effectively enough. A number of times Tello wasted the ball as he tried to beat defenders, only to over-hit his touch and run it out of play.
Therefore it was not until the 26th minute that Tito Vilanova's side eventually threatened their hosts' goal. Thiago Alcantara dribbled through the centre of the park, riding two challenges before striking the ball but his effort crashed off the bar and went behind.
Barca were lacking fluency up top but it was a swift break after Pedro Leon's scuffed volley was saved that enabled them to break the deadlock in the 32nd minute. Cesc skipped past Alberto Lopo before slipping the ball to Adriano and the Brazilian swept it under the keeper.
Thiago almost doubled the lead two minutes later as he controlled a cross on his chest in the area and volleyed the ball at goal. Moya, desperate not to be beaten again, dived down to his left and clawed the ball away from the bottom corner.
The momentum stayed with Barcelona after the restart but again they seemed limp in attack. Tello spurned two chances to add to his side's tally before the hour mark and so Vilanova brought Messi into the action.
The visitors were awarded a spot-kick in the 74th minute as Pedro cut inside of Juan Valera and was brought down by the defender's trailing leg. Messi stepped up to take it and, although Moya got a hand to it, he converted straight down the middle.
Messi then added gloss to the scoreline by scoring his second in the 78th minute as he tapped in at the back post after Pedro's cross was deflected into his path.
Almost instantly Getafe pulled one back as Pablo Sarabia's shot took a double-deflection off Adriano and Mascherano, and flew in at the near post with Victor Valdes nowhere near it.
In order to atone for their errors, Barca continued to attack and they scored a fourth before time was out. Villa, emulating his feat of scoring from the bench for Spain last week, latched onto a ball over the top and slotted the ball under Moya.
Though the result may have been somewhat flattering for Barcelona, they moved back to the summit of the league with a two-point advantage over their nearest rivals, Malaga.