>Betty Boop called Snow White?
This is correct.
The ghost character is known as "Koko the Clown"
https://en.wikipedia.org/wiki/Koko_the_Clown
I read in to it partly as the clowns were being exposed by the ghosts (mil intel).
Also, if you watch the video, the mirror is called the "looking glass"
https://www.youtube.com/watch?v=cKOSJ5AAwfc