I haven't honestly thought about this question, as I was brought to Disney early as my parents (when near my age) and their parents on my Dad's side (when also nearly my age) were all fond of the parks.
But, I don't think I feel in love with the Parks first, even though my first Disney Memory was the Monorail and Contemporary (at about age 4, before moving overseas).
What solidified it, I think, was the Sony Beta machine my Dad bought while we were in Germany.
As an American in Germany in the 80s, there was only so much english speaking content to watch. And while I would watch German shows from time to time, and even enjoy them, AFN (AFRTS) was our only English speaking channel. And it carried great shows like Star Trek. Another staple was the video rental store, which, back then, carried Disney Rentals...which my Dad dubbed onto Beta tapes. And so, I grew up with "gold beta" releases of Disney short cartoons. But there was one tape above all that I loved...
It included a short story of Walt, and how he made Mickey on a train ride...which led into Steamboat Willie. It also included, as I recall, shorts like Lambert the Sheepish Lion.
That was my true introduction to Disney.
When we came back to the US, I hated it. I hated the people, I hated the place, even though I am American. My grandparents lived near Disneyworld, and started taking me on every summer...and eventually taking me there (with a shady "annual pass" for me)...
About 13 or so, I knew I wanted to be part of it, and at 16, I applied for a part time job.
Never got that job, but the rest is history.