As a few others on here have said, FLCL is undoubtedly the best.
But of the ones listed.
Dragonball-
Original: It was okay.
Z: Set the standard for the crappy Shonen Cookie-cutter Jump action anime.
GT: Took everything that sucked about Z and cranked it up to 11.
Kai: Streamlined Z, but still sucks.
Naruto: A downward spiral of suckage. It was "okay" at first, but is too damn long, and the filler, oh god, the filler.
Bleach: Cheap, Yu Yu Hakusho rip-off. Needs to burn in the fires of hell.
One Piece: Pretty good all things considered, but no where near the best.
But of the ones listed.
Dragonball-
Original: It was okay.
Z: Set the standard for the crappy Shonen Cookie-cutter Jump action anime.
GT: Took everything that sucked about Z and cranked it up to 11.
Kai: Streamlined Z, but still sucks.
Naruto: A downward spiral of suckage. It was "okay" at first, but is too damn long, and the filler, oh god, the filler.
Bleach: Cheap, Yu Yu Hakusho rip-off. Needs to burn in the fires of hell.
One Piece: Pretty good all things considered, but no where near the best.