Alright, my next idea is to close all programs that do not need to run as for some crazy reason they might be crashing your PC while you try and update. From instant messengers to video games and anything in between, they all have to close, I suggest hitting ctrl+alt+del and then going through the task manager and closing all programs that have names you are unsure of. If you need to know what the program is that is running type the process into google. Also go to run on your start button and type 'msconfig'. Do basically the same thing you did with the processor list. After all that reboot. With a clean run try and give the update a go again. If your PC crashes once again, then it may be a virus. From there I recommend either going through with
HijackThis Log file or formatting your PC. Let us know how it goes

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