The Windows-based Ubuntu Installer, or WUBI, is a fantastic little program. The idea is this: you put in your CD or other installable media with Ubuntu on it while you’re inside Windows and WUBI autoruns (or you can select the executable if you have autorun turned off like you should have). It gives you the opportunity to install Ubuntu without partitioning or formatting, and makes it behave like a program, which you can install should you find it not to your liking. It’s a dead-simple tool for people that are either new or don’t know how or want to partition their hard drive. I cannot reccomend this highly enough, especially to people who want to experiment with a new operating system.
WUBI is available on the official Ubuntu ISOs. To download your copy of Ubuntu, go to ubuntu.com/download