well i use vitraul box from sun its not a memhog nice config options and best of all its FREEE :D but what you want do is find the Virtualization software u like best downlaod and install it. If you use Virtual Box be sure to specify where you want your VHDs and VMs before you create your first system because after that its a little more tedious. So after you have configured your Virtualization software download your fav liunx distro iso and install it on your newly created VM. If you have any futher question everybody here is pretty helpful
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