The first rule of the Usenet - you don't talk about the Usenet.
and
b) I only used to read the newsgroups and download various Linux distributions
Here's is slightly outdated, but still relevant info:
Slyck.com - Guide To The Usenet Newsgroups - QuickStart
I highly recommend going with dual machine built out - media server and client. Media server can be easily and cheaply built from common parts. It's doesn't have to be very powerful at all.
Newer versions of Freenas with plugin system is a great way to get media server setup pretty easily without much linux knowledge at all
For Media client aka HTPC - OpenElec with XBMC is truly awesome. Highly recommend it