I have not a great experience of Win10 (although I have a partition with Win10 on the Win7 PC but I don't use it often). But I follow the RSS feed of
The Windows Club, and although they are real M$ enthusiasts, almost every day they reveal a new problem with Win10. In the other hand, Win7 is old, but without the garbage of the new Windows "universal" apps, and totally stable (although they have made a questionable update recently). Anyway, on my machine, I can't reproduce the x264 problem. I must agree that that doesn't mean that it is more stable because the problem might be caused by other things (the CPU for example), but in the absence of another explanation, I must accuse the OS.
According to the x264 authors themselves, 2-pass is slightly less good because specifying a bitrate constraints the encoding between rigid walls. CRF use exactly the same encoding algorithms, but without any constraint. It is therefore free to use the most appropriate bitrate during the whole movie. 2-pass is of course much better than 1-pass ABR because the first pass is used to evaluate approximately what bitrate to use for the different parts of the movie, but it cannot predict exactly the final bitrate. Hence the slight quality difference with CRF. Unfortunately, there are many web sites that suggest to use 2-pass for the best quality, but it's because they are not well informed or their suggestions apply only to encoders without CRF (like the old encoder of DVDFab that had only 1 or 2-pass). Anyway, I just wanted to suggest to use CRF to avoid the crash during the second pass. You are of course free to use 2-pass if you want.