You cannot disable Windows 10 updates. Period.
Recently there has been news of two very serious security flaws known as Meltdown and Spectre. Basically the flaws allow malware to take advantage of how the CPU are designed to execute instructions (branch predictions) which can be used to monitor your activities, steal your information, execute "illegal" codes, etc. The updates will cause performance issues; the older the CPU to bigger the potential performance impact.
For companies running servers the performance impact could be up to a 20% to 30% decrease in performance. According to Intel, I believe they estimate that typical users should have something like a 6% - 10% performance impact; but it depends on what you do.
Here's a...