Linux is a great operating system -If you know how to use it-, and most people don't really want to be bothered installing, and whatnot, but it's really not hard to install, and if you use it often, it'll start being extremely easy to use.
The picture is my current desktop configuration, and I'll go through the programs I used to do that.
Step 1: What is this "Linux"?
These different Linux options are commonly called "distros", and some of the most popular are Ubuntu, Fedora, Debian, and Linux Mint.
These "distros" can be downloaded in .iso form, which I'll go into detail about later.
I'll be using Linux Mint for this instructable, so I'd recommend if you did too, but you're free to pick whichever you want.
(I'd recommend distrowatch.com for looking for a certain type of linux distro)
Step 2: Downloading and burning
To download, pick the distro of your choice, and if you know that you have a 64-bit processor, download the x64 edition, but if not, just download the universal (32-bit) edition.*
After a few hours of downloading, you'll wind up with an approximately 699 megabyte .iso file.
What you need to do is burn that to a disc.** To do that, you can use MagicISO, and the process is pretty straightforward. If you need help, feel free to ask me in the comments section.
*The 32-bit (aka x86) works with x64, however, the x64 does not work with 32-bit
**You can use a program called "Unetbootin" to boot off a flash drive. I won't go into that in this instructable, I might do it later though.