Hello all, I am looking for some advice.

I have a 5 or so year old Dell Power Edge server. I have used it primarily for messing around for esxi VM's. I wanted to set up a mining server. What are some easy to mine coins that I could start with. I am not looking to turn a profit per se, just want to learn the in's and outs of cryptocurrency mining. There is no GPU on the rig it's just a quad core xenon at 3.4 ghz I believe. Am I better off running it as a VM or just install an OS on the server and run it that way? How much electricity will this draw going 24/7?

TLDR
I have a free server and want to dick around with easy to mine crypto currencies but have no idea where to start. Not looking to profit looking to learn.