[@The Fox Without]ToX2 is such a feels game, but even more so when you 100% both sides of the first one, so the impact is even harder. 

[@Aquaknight]I only watched the anime, but... I can tell you that part 1, is 9 episodes. 
Part 2 is the remainder of that season.

And for some reason, Part 3 is 46 Episodes. 

Part 1 - Phantom Blood.
Part 2 - Battle Tendency. (Battle Tendency is just about perfect.)
Part 3 - Stardust Crusaders. (Though I did like this one, I wasn't the biggest fan of stands, Hamon is just so much cooler. Though it is why you have the Persona series. Not making this up either.)

Part 4 - Diamond is Unbreakable. (I am waiting for it to be finished before watching this. Hell, I don't EVEN like anime. But I love Jojo.)