"Windows Update" is part of your own Windows PC, I "Check for Updates" every so often, or when an icon displays, run most updates manually ... I have only ever "Hidden" 2 updates, one being GWX GetWindows10 (KB3035583)
I use MS Security Essentials, and install it's optional security updates everytime
I run Malwarebytes once per week and update the database everytime
I run Glary Utilities and update its version everytime I run it
Glary scans for malware, defrags, and optimizes you PC
I used to waste money on Norton, and Spysweeper ... and most payware antivirus are fancy animated GIF's "All Show ... No Go"
Free AVG is no good for me, and other freeware antivirus are much too intrusive, and take control of your PC, deleting Trainz, all because "IT" thinks it's a threat