"More Famous" is an arbitrary concept. There is no way to properly gauge which one is known by a majority of the general public without doing extensive polling.
Since that data does not exist any answer provided by the participants of this site would only be opinion based and not a substantial answer.
Muhammad Ali is more famous in terms of boxing
muhammad ali
Mohammad Ali is more famous.
Darth Vader is way more famous than muhammad ali, here is the proof have you ever seen a costume of muhammad ali? NO,exactly.
Mario
Batman
Muhammad Ali was famous for being a Boxer and was a world boxing champion.
yes
bruce barlow
Muhammad Ali of course ,because Shrek has gone out of style and Mahammad Ali has billions of fans worldwide.
Lady Gaga.
Probably Depp.