Piwik Upgrade *best practice*

Hello,

I am a customer of DreamHost who offer a 1 click install of the Piwik software. After installing I learned that I now have version 2.2.2 which is outdated. While in my dashboard there is a message with a button that allows you to update to version 2.8.3. I pressed the upgrade button and got an error and couldn’t figure out how to fix it because I am unfamiliar with the software.

So what is the point?
I uninstalled the previously mentioned instance of Piwik and I’ve reinstalled another 1 click version. What is the best way to update from 2.2.2 to 2.8.3 without any problems?

I am sorry if this question has been asked but I couldn’t find it.

What is the most recent and stable version of Piwik?