Your question cannot be answered with the information currently available.
"More Famous" is too idiomatic for anyone to provide an adequate answer without poll data from various areas & age groups, perhaps even from different socio economic groups.
Without any data of this sort there is no way to really determine which person is more widely known to the general populace therefore any answer would really be speculation, opinion and/or conjecture from the individual who answered.
walt disney is more famous
Walt Disney is more famous than Madonna.
Walt Disney.
Walt disney
Walt Disney!
Disney!
Walt Disney is more famous because its been around for longer and more people know what it is.
Definetly Walt Disney because Walt Disney is extremelly better and appeals to everyone and not just sexist adults.
walt disney is because many little kids grow up watching it
Well this doesn't exactly have an answer as Shrek is a movie and Walt Disney is a film maker.
Walt Disney was famous for creating mickey mouse and Disney.
mickey mouse