"Virtualizing the operating system and running it from a removable storage device has its advantages but it will not pull you out of a jam in case the host operating system is damaged.
"If you plan on rescuing data off a Windows-running machine or if you simply feel the need of an alternate operating system then Linux seems to be the solution. There are plenty of distros to choose from, with Ubuntu reigning over them through its ease of use and flexibility to run both installed on your machine as well as from a live CD."
