As I've said several times - if it's unplayable get a refund. What I do not agree with is people getting several hours entertainment out of a product and then saying they want their money back. I feel sorry for the guy that got 50 hours in and couldn't continue, but actually it wouldn't have been the end of the world if he'd had to start again, would it?
People on here constantly complain about the generic shooters and lack of innovation in the industry. Hello Games have done something incredibly brave and ambitious, and deserve some credit. OK they haven't quite pulled it off. They could have rolled out Joe Danger 67 and watched the money roll in if that's all they cared about. But instead they took a risk. This group mentality of witch hunting and actually encouraging people to refund (when many of those people have confessed to either just not liking it or having a couple of annoying crashes) will ultimately lead to less risk taking.
If you booted the game up, it won't run and it's unusable, get a refund. Particularly on PC, this is not unusual, many games just don't work on some hardware. If you just don't like it, think that having to restore your last save every now and then after a crash or are jumping on the bandwagon because you're bored of the game - perhaps wait until your next pre-order is in the bargain bin before buying, eh?
This is not a white good, this is media, a form of art. Different rules do and should apply.