Van Nistelrooy, 27, was regarded as something of an injury risk when he signed for United as he had been set to sign for the club in the summer of 2000, but broke down with a knee injury and the deal was put on hold for a year.
As a result of this, he was put on relatively modest wages, believed to be around £35,000-£45,000 a week, with the reassurance that the original five-year deal would be reassessed halfway through.
The striker's goalscoring consistency has seen him linked with big-money moves to Real Madrid and Chelsea but United are determined that he will spend the rest of his career at Old Trafford.
Van Nistelrooy added: "All I want to do is spend as much of my career as possible at United before I eventually return home and bring the curtain down with PSV.
"I want to be part of this great club and stay a part of it even when I eventually have to walk away. If you want to be part of history then you have to embrace the past. To be a legend you must learn about the club you are with."
Sir Alex Ferguson has set his sights on finding striker cover for van Nistelrooy during the transfer window.
The Dutch striker, whose fitness is crucial to United's bid to win the Premiership and Champions League, has been partnered mainly by Diego Forlan, Ryan Giggs and Paul Scholes this season but neither is thought to be an ideal long-term partner.
Ferguson has already had a £5m bid for Louis Saha rejected and has also been linked with moves for Mark Viduka, Alan Smith, Jermain Defoe and Real Mallorca striker Samuel Eto'o.
Meawnhile, van Nistelrooy is fearing a much tougher challenge from Aston Villa on Sunday than he encountered the last time his Manchester United team-mates took on David O'Leary's men.
The prolific Dutchman scored twice at the beginning of last month as United cruised to a 4-0 Premiership win at Old Trafford.
But Villa have bounced back from the setback in impressive fashion, earning 10 points from their last four league outings and bagging a Carling Cup semi-final date with Bolton by dumping favourites Chelsea out of the competition at the quarter-final stage.
"I expect this to be a very hard game," van Nistelrooy said. "Aston Villa have not been defeated since the last time we played them and no doubt they will want to continue that good run."
