It's better to ask your hosting provider about OpenVZ or KVM and consider your budget, both should work fine as long as minimal requirements are met. 

I think It's better to choose the control panel you are familiar with. 

We use Ubuntu and most documentation samples are written to use this OS, however some instructions are for CentOS due to popularity of this system. So I would suggest to use Ubuntu - the latest LTS version or CentOS. 

Also you can consider to use our UNA Cloud - https://una.io/page/hosting