I'm unsure how to ask this question, but I'm switching hosting companies and got to migrate everything. I'll probably set up everything up manually, no copy paste work, except the regular files. However, my old server was set up with Ubuntu 12.04, the latest one available at that time, but at this very moment, Ubuntu 14.04 is released. Now I'm unsure whether I should stay on 12.04 or upgrade to 14.04 for performance/security or other relevant reasons.
I'm not a server-programmer, but rather a front-end developer, so my command-line skills are equal to my google-search skills, and I think I have to do equal amount of searches to get everything working on Ubuntu 14.04 as for Ubuntu 12.04.. (Oh, and I'm not paying for a support plan, so got to do everything by myself)
Although it might be opinionated answers, please answer based on as much facts as possible, as regarding the StackExchange rules.
Thanks in advance!
Description of the server content
A server with a Zpanel Admin Panel (which requires 12.04, so 14.04 wouldn't be an option, but still interested!) and a MySQL database of course. I will be running static websites on it and WordPress too. I als will run an Email server on it via DoveCot/Postfix.. So it's pretty straightforward, I guess, nothing extraordinary or special.
Best Answer
Performance is largely dependent on the actual application you're running. If there's specific kernel improvements in the area of performance you'd like to take advantage of you can leverage the LTS Enablement Stacks for a later kernel version and associated programs
Given that 12.04 is an LTS edition, any security fixes in supported packages will be backported to 12.04.
In order to minimize risk and changes in your environment, I'd suggest sticking with 12.04.