I actually ended up just going with a fresh windows, and currently only installing programs that I really need so hopefully none of them will cause any strange behavior.
I re-downloaded all drivers in their newest versions for this too, so everything should be up to date now. Since installing, on friday I believe, I did however have one BSOD.
This happened within a few minutes of Guild Wars 2 crashing on me though, so I was thinking that it might have something to do with that.
That particular crash was caused by this (quoting from the crashlog)
Assertion: Encountered draw command outside of draw batch
followed by a BSOD with bug check code 0x10E.
There is a fair amount of information in the Guild Wars 2 crashlogs, so I'll just put them in the .zip file along with the crash dump from the BSOD and the other files, in case you want to take a look at that. (It is a fairly new game though, and there are other people with crashing issues, so this might be unrelated and just buggy code)
Other than that, the system has been running fine so far, no other BSODs (yet).