Performances:
Let's say you are running Pentium processor + 2/4GB RAM or so, I would highly suggest you to use Win XP or 7.
Otherwise, if you have a fairly decent CPU such as I3 - second generation with
at least 8G RAM. Win 10 is the way to go.
Please
do yourself a favor and use SSD if you are planning to use Win 8/10 which will allow fast boot - one of the greatest feature of Win 8/10.
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Privacy:
I would highly suggest Windows 7 if you want something on-the-go (no setting needed). Windows 10 will be just fine if you turn off privacy settings. How? ->
https://www.makeuseof.com/tag/complete-guide-windows-10-privacy-settings/
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Anti-virus:
If you are a PC noobie (don't know which installers/websites are trusted), I would advice using Kaspersky or alternatives and Malwarebytes (free version is more than enough). However, don't be surprise if one day you see your AV takes all your PC resources.
If you are confident about your PC skills, Windows defender + Malwarebytes free works just fine.
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Any others?
- Please make sure that you don't run any auto-update, if your computer works, just let it be. Running auto-updates could get your PC crashed randomly.
- Remember, latest is not always the safest. Takes researches to see if the last update has any glitches or not, something always breaks after the new updates lol.
- Wanna update? go to Microsoft mainpage and read about update logs, only install what you need and be sure it's compatible with your Windows build.
- Windows 10 is the closest thing to OS X at the moment

- Something go wrong? Make sure you choose the correct installer + do some google search around your issue, there will be a fix eventually.
- Ask me if you need further information
Hope this help
