Let me define "wide appeal" then, Flippeh.

1. The music. Oh [s]man[/s] lion the music. If
Can You Feel The Love Tonight's rank in the pop charts has anything to do with it, it's that people simply love the music.
2. The message of the movie. Producer Don Han said in many interviews and videos that one event that really got him with the movie was the birth of his daughter. Suddenly the movie didn't just apply to other kids growing up, but the movie had a lot to say to him as a new father.
3. ^ The fact that The Lion King not only had a story for the kids, but it had a story for the adults as well.