Wubi looks promising: it's an installer package that lets Windows users install Ubuntu Linux like any other Windows app, without worrying about disk partitions and whatnot. I've used Ubuntu exclusively for more than a year now (and yes, I know, I owe you all a "What Ubuntu is like" post and I'll get to it RSN), and Wubi sounds like a low-threshold way to get people to try out life on the free and open side.
Wubi is Safe
It does not require you to modify the partitions of your PC, or to use a different bootloader.
Wubi is Simple
Just run the installer, no need to burn a CD.
Wubi is Discrete
Wubi keeps most of the files in one folder, and If you do not like, you can simply uninstall it.
Wubi is Free
Wubi (like Ubuntu) is free as in beer and as in freedom. You will get this part later on, the important thing now is that it cost absolutely nothing, it is our gift to you…