I case anyone is interested, I have Plex up and running now and wife is happy, some feedback on how it went

Why it went:

• I needed to install Plex specifically, because all the set-top boxes we use support plex but are fairly locked down. Wife likes their interface and remote control and doesn't want to change (they are simple to use< Australia Telstra boxes, all free)
• I choose Mint, I thought I'd prefer a GUI to make the install easier and also wanted to see what Linux desktops were like these days

How it went

• Install was trivial when I chose "simple" - I tried advanced to format the two drives I had (which were messy with many partitions I wanted blown away), but when I tried one method it told me I had a Boot drive but no NIF or NEF drive (or something) in order to boot - when I told it to install that type (Found it in the list) it told me I had no boot drive now (Online help for Mint install on Mint web site was out of date and the GUI didn't match what I saw - a common theme - so made it harder) - Gave up, choose SIMPLE. No idea what it installed but it worked
• Lot more raw command line that you'd expect from a GUI, In fact not sure the GUI does anything at all. I used the command line commands for almost the entire install
• The Networking failed and was as bad as Windows off the bat. HOWEVER fixing any networking issues was much easier than windows (I still have network issues in my windows machines from 5 years ago, never could fix them) but the two issues I had with Mint, (1) plex could not be seen (answer: ufw opened one port) and (2) Windows could not see and share a Mint drive (answer: Samba installed with one line and permission set on a folder) were fixed in a few minutes
• Man you can trash your OS with one command! Reinstalled once because I did a chown on the wrong folder and gave plex the sole ownership of the entire drive whereupon nothing ran anymore!
• Much faster, better software generally, the trans-coding for videos seems better, the speed of the desktop "server" is faster and Plex is madly playing everything nice and clearly with great response time.
• Stuff changes a LOT between versions apparently- many suggestions online failed for me because the suggested folders or files no longer existed or had been moved or changed. Likewise Mints own sites screen shots doesn't match reality.
• People are confused a lot - One of the common issues is Plex cannot see the folders where your videos are, as Plex runs under its own user - The number of different methods people have used to get around this is outstanding! And every one is thumbed up as "the answer that solved my problems!" From changing the user Plex uses to root or other users that already have permissions, to adding plex ownership of folders or even changing permissions of the folders to either something safe, or just ROOT ROOT ROOT. It is hard to know what you should be doing (Even changing permissions there were apparently at many programs to use, not sure which was the right method... chown, setfacl, chmod (I know they are different, I glanced at the docs but with so much to learn it becomes a bit overwhelming and you just take the first suggestion and stick with it)

Edit: at any rate, works fine now ty all for suggestions. Now I am getting annoyed I don't have ALL the services running on the server and am starting to see what else I can run and how.. all without interrupting my wifes streaming of course!