I would just choose Nala, Simba, and Scar, but there is no option for that, but this will do as a lot of the characters other than them made it memorable too.

The majority.

Think about it: you can mention any character's name without having to say "The Lion King" and people will automatically know what you're talking about.

Pretty much this. I think all the characters are really memorable, the film has a strong cast of great characters! I feel the same way about the songs too - all of them instantly remind me of the film as a whole.

Mufasa Simba Nala all of them!!!!!!!!!!!!

she's my sweet beloved Nala i'd be so sad if she was forgotten