When I got my last computer I opened it and made a restore point. Then I set it up the way I wanted and made a second restore point. Then I made a complete image backup of the entire computer on an external HDD. Then I protected the entire computer with Deepfreeze, which prevents any changes to the entire computer.
I use a separate HDD for downloads that may be infected with anything and only connect it to my computer when in the frozen mode in Deepfreeze. This way my computer can never get any viruses and I have a complete backup of the entire computer. Every six months I reinstall the previous computer image, make any changes and updates and immediately make a fresh new image. I do this twice a year and now five years later my computer is fresh as new and totally updated.
I only thaw the state of my computer every two days to update anti-virus and if need be I go on the Internet with a sand-boxed web browser. Solves all my computer problems!