Searching and reading is always good advice.
Install linux somewhere. You'll want something to get your hands dirty with. (More on that later.)
My curiosity and specific desires drove me into what I researched and learned.
I use some programs that use "a lot" of resources. Therfore, while my computers have "plenty" of RAM, I wanted a light desktop environment. So I researched "Desktop Environments".
"Oh look, there is a difference between Desktop Envirnoments and Window Managers. Interesting."
When I learned about Openbox I installed it. It needed to be configured
<- that forced me to research and learn about editng configuration files.
Configuration files can exist in various locations throughout the Linux directory system
<- that forced me to learn more about the Linux directory system and navigating through it.
Actions within certaiin directories can only be done as root
<- that forced me to learn about "sudo" and the appropriate terminal commnads
<- that forced me to learn about terminal commands. (I was already interested in the terminal, though.)
Long story short: I started with Trisquel about 5 or 6 months ago. It did much of everything for me. Today I am essentially running Debian sid with a Minty undertone. (I think I found my distro.)
I used to be interested in the lightest
gui file manager. Today, the terminal and Midnight Commander are my primary file managers.
Back in the late 70's and 80's personal computers were new and exciting and you could do what you wanted with them. Windows, MAC and patents took that away. Linux brought the excitement and "exploration" back. It's a whole new world.
Your own curiousity and time constraints might lead you down a simialr yet different path, but you have to get your hands dirty.
As actor / comedian Stephen Fry has said, "Use a GNU/Linux operating system on your own computer." You will find a virtual universe to explore at your leisure.
http://www.youtube.com/watch?v=P_mS4CIXcLY