I usually prefer Ubuntu LTS versions. Centos is also good.
There are a few reasons on why I choose Ubuntu
Regarding NodeJS + MySQL, I would suggest you install MySQL on a separate machine so that you can horizontally scale it in future. If that's a small app, leave it.
DigitalOcean is my favourite VPS provider. My referrel link: m.do.co/c/ad8373126036 (you'll get $100)