Screen flickering on Windows 10

[Tairetsu]

So, my dad upgraded his laptop to Windows 10 yesterday or so, he says that it was working fine at first, but when he turned the thing back up it was doing this:

 

 

I'm not sure what it is, I've never used Windows 10, since I haven't been able to upgrade myself yet, and since he lives quite far away I cannot get my own hands on it, so I'm going to have to tell him what to do step by step, but for me it looks like explorer.exe is crashing and trying to start over and over again, he says, and like the image proves, that he cannot click the start menu button, nor open it using the windows key, but says that pressing ctrl+alt+del does work.

 

So I don't know, for one thing i'm not sure what the issue is and i'm not sure how he could fix it, I haven't told him to try and start the computer on safe mode, but I would like to get some idea of what it could be before trying anything, the only possibility I can think of right now is rolling back to Windows 7 but I don't know how you would do that.