Linux Mint
The front page is a soup of meaningless babble. The installation guide is in programmers documentation style and split over 15 pages.
Literally the same amount of effort and level of complexity as installing Windows.
I understand as a software person it's hard to have a generous perspective when trying to distinguish between "confusing only for the hopelessly computer illiterate" and "potentially confusing for regular computer users", but we should try to err toward giving people the benefit of the doubt.
If that's incomprehensible to someone, then they're probably not going to be installing any operating system by themselves, Linux, Windows, or otherwise.