There's an awful lot of campaign settings out there, so most of the choices are "official" ones. "Other" covers all 3rd-party campaign settings.
However, if there's a third-party setting you particularly enjoy, let's hear about it!
My favorite setting's Greyhawk.
Most of my early Dungeons and Dragons experience was participating in Living Greyhawk adventures in middle school. I also ran Paizo's Age of Worms Adventure Path several years ago. I had some real fun with it, and it was this adventure path that my group and I first experimented with the really
unbalanced stuff in the game: the party Cleric used Divine Metamagic to one-shot Dragotha, a major dragon-lich villain near the end of the campaign. In the adventure before that, the sorcerer was Fingering of Death
several big dragon encounters. Big, bad-ass, mighty dragons, all dead from a single spell.
It was fun in a weird way, tearing apart the system and making a cakewalk of many dangerous encounters.