A long while ago someone gave me pretty solid advice, and it applies to choosing the OS for both a server and a personal computer: go with your friends’ religion.
I say that, so when we say go with Ubuntu, we aren’t saying it because it is particularly better, but mainly because we all use it and therefore will be more capable and inclined to assist you. ![:slight_smile: :slight_smile:](http://archive.v1.talkgroup.xyz/images/emoji/twitter/slight_smile.png?v=9)
Of the distros available from Digital Ocean, you can safely disregard FreeBSD and CoreOS. They are fine systems, but for your purposes you want to stick to ones that have tons of docs that cover your use case. CoreOS (which I believe is now called Container Linux) is for, well, containers, which is overkill for a website like yours. FreeBSD is a different flavor of UNIX-like spice, and while parts of it are in your Mac, it has a specific community and use cases that aren’t focused as much on WordPress hosting.
That leaves the other four (from your screenshot), and from those you have two families: Debian/Ubuntu and Fedora/CentOS(/RedHat).
Fedora is one of my favorite distros, because they are opinionated in the same way I am with the desktop, but their web servers have defaults that I find difficult to configure, in part because I don’t use it very often. CentOS is an enterprise-y version of that, and both of them are part of the RedHat family, which is cool because RedHat is one of the most successful open source companies in existence. If you going with the OpenShift platform (more containers!), I would suggest checking it out.
Finally, Ubuntu and its awesome parent Debian. Debian is a popular and useful project, and Ubuntu is the mainstream version of it, created by Canonical to appeal to computing consumers. For a very long time it was the most popular distro, and since then all the popular distros have been based on Ubuntu, so that is saying something.
Ubuntu as a server is a very popular choice, in part because developers were using the desktop personally, and also because Canonical marketed and partnered the hell out of Ubuntu, and nearly any web app will run, with specific support for Ubuntu.
That is actually why I use it: over the years as I ran into an issue for either my PC or a server, almost all the solutions are for Ubuntu, and sometimes packages are available for Ubuntu in lieu of other distros. You are getting into web servers at an interesting time, when we are seeing alternative package managers for installing software appear, and leading the pack are snaps, the de facto choice for Ubuntu.
Anyhow, that was a long-winded mini-history on what all those distros are, but yeah, install Ubuntu. And stick with 16.04 for now, as it is the current Long Term Support (LTS) release, so it will be receiving updates until 2021. ![:slight_smile: :slight_smile:](http://archive.v1.talkgroup.xyz/images/emoji/twitter/slight_smile.png?v=9)