Out of non-biased, you'd have to say Freeza. Most well known villain in the universe even the gods acknowledged him, despite being easily surpassed by everyone later in the series.
In terms of popularity. Out of the big 3, I'd think it'd go Freeza > Cell > Boo. However, my preference is Boo > Cell > Freeza.
Who is the greatest villain in the entire series?
Re: Who is the greatest villain in the entire series?
I think piccolo daimao is the best villain. He is the first villain to kill off the main characters. He is the only villain to actually get his wish granted. He destroys the dragon, and truly strikes fear into people's hearts. Plus he looks really creepy when he spits out eggs.