Designated Hero: Fingal. Even before anything has happened, he regularly harasses his coworker because he finds her attractive (and the feeling isn't mutual, which even bleeds into his fantasy version of her). You can't blame him for being upset at how things go for him later, but that doesn't justify his actions. He fights against Novicorp even as they're trying to recover his body (even if they're only doing it to save their stock value, as explained in a scene cut from the MST version) and even after Apollonia explains that his actions in the computer are affecting the real world he continues to screw around just to piss them off. It's clear he didn't know just how widespread the damage was, but he still knew he was doing something, and considering the weather patterns mentioned, he had to have caused a massive amount of deaths. Even his original act of "rebellion" is wasting time watching movies on the clock; it's sort of half explained they've fallen out of fashion and he can't get them otherwise, but this is never really made explicit beyond his coworkers not being familiar with them. The conflict of the movie is almost entirely driven by the hero, and not one of the leaders of the implied corporate dystopia as one might expect.
Designated Villain: Novicorp and the Fat Chairman. He's definitely a Smug Snake and it's pretty clear that he has something big planned for when they've buried Lexicorp once and for all. ("WE. WILL. WIN!") But the movie doesn't spend a whole lot of time explaining any of that, so as far as the audience knows the Chairman is just kind of a selfish Jerkass at worst. He takes a mostly passive role throughout the movie, usually acting to keep Apollonia from giving Fingal too many ideas (which he's entirely proven right on). He gives Fingal quite a few chances to behave and simply wait for the problem to be fixed. Even when Fingal refuses to accept his final offer, the Chairman's reaction is only to cut Fingal off from the access he wasn't supposed to have anyway. It's only when Fingal immediately hacks back into the system that the Chairman actually tries to have him killed.