Is this a spare
computer? In other words, is it a machine that you can dedicate to learning Linux, while you continue to use Windows (or whatever) on some other machine?
If it is not, then the first
thing I want you to do is to buy a second hard-disk drive. (My main machine actually has three...)
They're not expensive anymore and they're easy to install. Most motherboards have two on-board EIDE channels, supporting four drives, and of course expansion-cards are cheap too.
On the main drive, "install what you know." If that's Windows, then Windows it is.
While doing this, gently unplug the power-connector from the second drive so that Windows never sees that it exists.
Now plug in the power on the second drive. Using the BIOS Setup screen, select this drive as your boot-device. You might even temporarily unplug the other drive if you are nervous about corruting it (at first). Install Linux on this drive. Any distro that you please. Try several!
Then... play with the system with no
initial expectations about being anything less than utterly bamfoozled
by it. When your head hurts, shut it down and do something else. (The computer, I mean ...
Seriously... Keep a diary. A loose-leaf notebook and a number-two pencil will do nicely. When you do things, jot it down. When you have a question or don't understand something, write it down,
and leave space for the answer. Once you have captured
in this way, you no longer have to go chasing after it "right now." You can come back to it at any time.
When you make a system change, print off a page describing it, three-hole punch it, date it, and add it to the diary notebook.
After you get past the initial feeling that everything you ever knew about computers just went in the trash ... after you experience the feeling that Bill Gates is a wonderful man and why would anyone
want to use anything else
... after your diary accumulates several dozen pages ... all of which you have expected and planned for!
... then, the pieces that got all thrown up into the air and which initially landed in a great big confused heap on the floor, begin to snap into place one-by-one. They begin to make sense. (Then they get thrown back up into the air again. It'll happen a few times.)
So you stick-to-it, and you remember what it really feels like to learn new things. And you start to seriously enjoy
it. (It was the feeling that you waited for.)