I have worked with computers for 30 + years, I do not shy away from trying things on the computer.
I used to be an expert at solving computer issues, when it was DOS, Windows 95/98 and even Windows XP.
Windows Vista and Windows 7 I have just not had the time to explore.
I generally think computers are too difficult for the mainstream user, too many options and too many ways to get in trouble. Add to that buggy software and faulty hardware, and I wonder how anybody can do anything useful on their computers anymore.
I look at the new smart devices and see how easy they are to use, then compare to a PC and it is like another world.
I am pretty sure if Microsoft wanted to make the PC virus proof they could, but, in my opinion, the virus detection and remidiation business is too big for that to happen.