Windows for me. I tried to be a Mac guy when I was in school but at that time I was poor and my friends could give me copies of windows programs I couldn't afford (Office, Photoshop, CorelDraw, etc.) so I went with a Windows based system. I can now purchase my software so I'm not a thief in that regard any longer.
As for Unix/Linux, just not technical/detailed/patient enough (nor do I ever want to be) for those OS's. Yes, Wintel probably crashes often but that's what I have ghosting software for.
FWIW, I sell Unix software for a living so I know what's involved to use & maintain a Unix system. It's not as easy for some as you would like to say it is.