What did the Clones think about Jango? I don't think any of them would of actually met him before his death, but my guess is they respected his combat skills but probably didn't think highly of his job. I'm interested to hear some thoughts on this.
I'm guessing they respected Jango for being their donor/father. But beyond that I'm not sure what they thought about him. As far as I know Jango never really interacted with them. I remember reading in a book somewhere, and I'm paraphrasing. "Out of his thousands of children, the only one he really cared about was Boba." Which was probably true.
ARC troopers knew Jango personally and I'm sure those who trained under Alpha (like Cody, Bacara, Gree, ect) were informed of Jango.
Mutual indifference for the most part. They'd obviously be cognitively aware that Jango Fett is the source of their DNA and understand the value of this inheritance from a technical standpoint, but that's about it. Had Jango survived the battle in the Arena, I have little doubt that the clone troopers would have gunned him down.... or would they? In many ways, Jango Fett is the "allfather" of the clone troopers, like Odin was for the Norse pantheon. However, seeing as the clones tend to be pragmatic, unsentimental sorts with indoctrinated loyalty towards the Galactic Republic over just some dude who gave them his DNA, that's not a view they'd likely have.
If I remember from the EU, some of them practically worshiped him, some of them thought he was a traitor, and some of them respected him as a warrior and as a man despite his betrayal of the Republic. Basically, their opinions of him were as varied as any other group of humans with distinct personalities. Now, as far as canon goes, I don't think we ever hear any clones express a specific opinion of Jango. But we know the clones are (mostly) unswervingly loyal to the Republic, so I'd guess most of their viewpoints would fall into the latter two categories, given that Jango worked for the Separatists.
For most I bet it was an "out of sight out of mind" situation. It makes me think though how much of Jango's ideas and Mandlaorian warrior culture got spread to the specialist clones he trained himself. At least one went rogue and formed a new Mandalorian sect. Some others were fairly in tune with Mandalorian culture.