I am trying to remember a strange cartoon "movie". The main thing that I keep remembering is there is a scene on the moon where people have these heads that can be taken off and switched.
I cannot remember if it is also live action, but I know that is is in cartoon format.

Sounds like

Fantastic Planet (73)
a.k.a. Le Planet Sauvage

Thank you straydog. This has been bothering me for a very long time. Thank you.