Hesitated to reply, but I do so...
Linux, Windows... are tools. These are complex tools you have to learn to know how to use them. A lot of people learned to use Windows as they learned to use a hammer : hit their finger then tried to not hit them again, but never learned correctly, while a carpenter pushes a nail with only a couple hits.
What I love in Linux is the choice. You choose the distribution first. A distribution is a set of programs chosen by a set of distribution developers and a way to manage these programs. Then among these programs you chose the one you want to play with and you can add more of course.
Among the programs you chose, there is the graphical interface. This is often something difficult to understand as with Windows you have the graphical interface from Microsoft and no other one. The graphical interface defines how the windows are handled and how they look. This is one of the most important thing to chose as this will dictate the way you'll have to work with the windows. I'm using enlightenment as I know how to configure it to optimize my work. Now I use a graphical interface to run a couple graphical programs (firefox & openoffice) but also to run tens of text terminals (xterm) permitting me to access remote systems that have themselves a graphical interface or not.
The other important thing is the way the Linux distribution manages the programs. This is generally done through binary packages and dependences. You say which program you want and the system installs all the packages the package you want depends on. But another thing often difficult to understand is that the programs installed by binary packages are compiled as the maintainer of the package decided to. This is why there is some distributions that permit you to decide how to compile things or at least to tune the compilation. I'm using gentoo as this is the distribution that let you the most choices, except the "diy" distributions. With some packages (noticeably with gnome and kde programs) I can decide to depends on tons of other packages (miscellaneous libraries, daemons...) or only a few.
Some distributions are more user friendly than others. Mandriva and Ubuntu are certainly those permitting a newbie to do most things. Then there is some more "professional" distributions with possibilities of professional support. Then there is some more "hacker" oriented distributions such as gentoo and Linux from scratch. Then there is more specialized distributions such as embedded ones, or education oriented ones, or games oriented ones, or...
So never talk about "Linux" as there isn't a single Linux. The single term Linux indicates the Linux kernel that is developped by Linus Torvald and hundred of other programmers. This is the single thing which is common among all Linux distributions, but each one compiles and tunes it differently.
The guy that made me discover gentoo is using it in ways totally different from mine and I certainly can't use his computer without having to tune it as I like to use it.
Talk about a distribution, talk about a graphical interface, talk about a program...
Before all talk about choice because you have the power to choose what you want and how you want it.
Denis.