The on-loan Tottenham player was branded "silly" by Magilton after appearing to gesture towards disgruntled supporters during Rangers' previous home match.
But his stock rose considerably after just 11 minutes when he collected the ball on the left wing, strolled past a couple of Preston challenges and, from 25 yards out, floated a stunning curler over goalkeeper Andy Lonergan and into the corner of the net.
"He has that in spades, he's a genius," beamed Magilton.
"He's a dying breed in the modern game, the way he goes past people, and the finish was pure class."
Rangers gave their chairman Flavio Briatore something to smile about with a superb performance.
Briatore had shrugged off the doubts surrounding his ownership of the club to take his place in the Loftus Road directors' box for the first time since the infamous 'crashgate' scandal came to light.
The Italian, who is the subject of the Football League's fit and proper person assessment after being thrown out of Formula One, will have enjoyed the four-goal display.
Akos Buzsaky hit the second goal from the penalty spot after Neil Mellor felled Taarabt, and Jay Simpson and Wayne Routledge completed the scoring late on.
"It's our best performance since I've been here," added Magilton.
"We've shown glimpses of that in other games but we've taken our opportunities today. I thought we were excellent."
Rangers lost their captain, Martin Rowlands, to a season-ending cruciate injury - the second of his career - this week while he was playing for the Republic of Ireland.
"There's been a feeling of real gloom all week after Martin's injury so that win is for him," said Magilton.
"It's heart-wrenching. We've all come together as a team and as a club. Our performance today was great and we'd like to dedicate that to him."
Preston boss Alan Irvine was left to rue a missed chance from striker Chris Brown with the score at 1-0.
Brown found acres of space in the QPR penalty area only to see Radek Cerny tip his angled shot around the post.
"Goals change games," said Irvine. "That could have been a key moment. But QPR were the better team overall.
"They've got a lot of good players and I expect them to be challenging, certainly in the top six, this season."