You should probably mention that your sig is from a movie and that the animation will never look that good.
If you like fighting more than story I'd go with Bleach.
One Piece
You won't get a decent fight in One piece until like 200 episodes in (not joking). The story takes way too long to get
interesting. They drag things out more than anything I have ever watched and they add filler parts to every episode to drag it on even more. I suggest reading the manga until the Water 7 arc. Also each character you meet has a 10% chance of being cool and a 90% chance of being really ugly and annoying.
I'm not hating on One Piece, when it gets good it gets really good. Just giving you a warning because the first 1/3rd of the series it really boring.
Bleach
If you watch Bleach I suggest you watch the first episode then skip to 18-20 because the first episodes are pretty much filler. Though most of the fighting in the first arc is just super generic:
Bad guy: "How are you still fighting?! you should be dead by now"
good guy: "I'm not going to let you hurt my friends!!(super bullshit powerup)"
Bad guy: "Oh nooooo"
Another annoying thing is that Bleach's characters are all unable to die. I honestly don't think one good guy has died throughout the entire anime.
And the fight against the final bad guy is incredibly disappointing.
So Bleach has better fighting, One Piece has better story and IMO is better overall. But it takes forever to get good.