If you're looking for a safe and easy way to test out the switch from Windows to Linux, Wubi might be the program for you. Wubi's dialog interface requires users to select a mere six options to install Ubuntu, but don't expect direct help with this utility. Users are expected to have a basic understanding of Linux and booting into alternate operating systems, and you'll have to rely on the Wubi FAQ and forums for assistance.
Selecting the install drive, hard-drive space, language, username, and password is quick with pull-down selectors. The most difficult decision is choosing the environment from Ubuntu, Kbuntu, Xubuntu, and UbuntuStudio, and you should do your research before making a selection.
While this is truly a one-click install of Linux, it isn't fast. The first step downloads an almost 700MB ISO image used to install Linux. After the download, the app takes a considerable time unpacking and installing the operating system. Boot into Ubuntu, and there is another wait as the OS completes setting preferences and options. It is all without user intervention, though, and the numerous preinstalled and preconfigured apps make the switch to Linux about as painless as you can get it.