I've gotta say Ubuntu here, even though it's kinda looked down upon by a lot of Linux power users.
I just want an operating system that works out of the box for the most part. I don't want to be spending hours on getting simple functionality to work, which is what you're up against when you pick a more open and customizable distribution, like Arch for example.
Installing drivers is generally very easy and there's a lot of support for any issues that you might have. Aside from that, I kinda like their UI, I've gotten so used to it that working with a standard Gnome or KDE window manager feels a bit weird.
For me, Ubuntu is a solid distro that offers all the benefits of Linux, while also remaining easy enough to use, like Windows or Mac.
Debian - because I started on Linux with a raspberry pi running Raspbian. I tried a few other distros, but being used to Debian I found them hard to get used to, so I sticked with Debian and Debian-based distros such as Ubuntu
I have to go with Mint,
Based on both Debian and Ubuntu I just prefer the UX and interface, experience better.
It was the first distro I was ever serious about (more than just playing around) so it is the one I tend to gravitate to first.
I prefer the Debian based Linux Mint.
Right now I am using Windows 10, and it has all the features I need, while making my life easier, but I prefer to use Linux as well. It's pure awesomeness.