The reason why Zoro dislike Sanji is because he treats women differently than he treats men, and ever since Kuina complained about being a girl, Zoro is set on the idea that gender should not decide how you treat a person.
The three admirals of the Marines: Kizaru, Aokiji amd Akainu are based on the animals that accompanied Momotaro (a Japanese folklore hero). The animals they resemble are a monkey, pheasant and a dog respectively.
4Kids was the second dubbing company to dub One Piece. However, many fans of the original Japanese version detested the editing many episodes and scenes in 4Kids's translations received (editing out all mentions of death, getting rid of cigarettes or replacing them with lollipops, cutting out entire arcs, adding unnecessary jokes and puns in the heavily edited dialog and more). FUNimation eventually acquired rights to dub the series from episode 144 onwards, and eventually obtained the rights to episodes 1-143. The 143 episodes which 4Kids did edit were edited so heavily that they had been cut down to 104 episodes.
In the 4kids version, the name of Captain Smoker is changed to Chaser, to avoid any relation with cigars (one of the many items that were censored in the series). While in the Funimation version, his name is changed back to Smoker and his cigars aren't censored out.