Mint is great if you want a Linux experience that works with minimal hassle. It uses the Cinnamon desktop environment that is similar to Windows UI. It also has lots of apps and settings that imitate Windows, so it should be intuitive. Ubuntu is also an easy transition for new Linux users, but not as intuitive as Mint, and it has been getting some critique lately for decisions made by the distro's developer (Canonical). The decisions are likely not going to make much difference in your daily use as a new user, so I wouldn't worry to much about that specific issue because Ubuntu is a great distro for new users as well. In fact, Mint is based off of Ubuntu. Additionally, Ubuntu Server is one of the most popular server builds because of its ease of use. If you are unsure, you can make a Live USB of each and try them out for a few days.

Tip: As a new user, it's possible that you will eventually make a mistake or change to your build that you would like to undo. To undo easily when the time comes, make sure you set up Timeshift when you first install your build. It takes snapshots at whatever regular intervals you would like so that you can revert back to one when the time comes. It has saved me lots of frustration.