The Transformers beauty became engaged to Green for a second time earlier this month (Jun10) during a romantic beach vacation in Hawaii.
The couple, which began dating in 2004, called off its original plans to marry in February, 2009 after a two-year engagement but reunited months later.
Fox claims being Green's fiancee again is "really not a re-engagement" because "nothing is different" - and the 24 year old insists she won't be walking down the aisle anytime soon.
She tells UsMagazine.com, "It's going to be years! I'm going to be 44 when I get married!"
But she admits the happy couple has made a start on wedding plans - and the former Beverly Hills, 90210 star is keen on having a say in all decisions.
Fox adds, "He is in on the planning. He wants to be!"