Linux is frustrating.
Okay, current issues:
1. Installed nvidia drivers. Cannot get any resolution over 1024x768. Also, control panel thingy (Nvidia X?) is blank. Tried an older driver, no change.
2. Folders aren't being shared. Installed Samba. Set it up, but it isn't visible on my network. Could be related to #4.
3. Hauppauge tv tuner isn't showing up as needing a device driver, but it isn't working either.
4. Plex can't see the libraries. Apparently, even after mounting the drives and seeing the folders, Linus still needs permissions.
Time to slay some dragons.
Make sure Samba is configured properly. Use something like this https://www.techrepublic.com/article/how-to-set-up-quick-and-easy-file-sharing-with-samba/
, or of course use the google.
As other people mentioned, I would install Ubuntu 18.04 LTS server, and use command line. Worth it to learn to use "apt" and "dpkg", and "cat /var/log/syslog|more" is your best friend when things go south (like right now). Installing the desktop GUI afterwards is always an option, if command line is not working for you.
I would expect Ubuntu to take care of Nvidia drivers at install as part of the install process. Surprised you needed to do a separate install.
Permissions always need to be addressed. "chmod 755 filename" for starters for the files you need to access (to get past the initial cursing phase), then tighten permissions as you get more Linux savvy.
Now you know why every year is the "Year of the Linux Desktop", and always will be, lol...