The origin of Disney is clearly from Isigny, and the use of the term "Of" Isigny or more correctly D'Isigny. When researching the name and the origins, D'Isigny is a distraction as it is no more than a description of where the family or clan came from. Thus, the accepted first "Disney" being Lambert wasn't Lambert D'Isigny, rather Lambert who came from Isigny. His son was Jordan or Jocelyn FitzLambert (who originated in Isigny) remember this is post conquest so Normans would tend to say where they came from. There might have been many "Of" of "From" Isignys in England during the immediate post conquest period, almost certainly all from the same clan or extended family, but not necessarily a sequence starting from Lambert as is seen in Burke's Landed Gentry. As to Norton Disney, maybe simply Norton until Sir William Disney who is interred there with his knightly effigy. It does not change the fact of the origin of the name.