WUBI

Wubi is an unofficial Ubuntu installer for Windows users that will bring you into the Linux world with a few clicks. Wubi allows you to install and uninstall Ubuntu as any other application. If you heard about Linux and Ubuntu, if you wanted to try them but you were afraid, this is for you.

follow this link ...

http://www.cutlersoftware.com/ubuntusetup/wubi/en-US/index.html