How to Choose and Install a Linux Distribution

Linux Distributions

CentOS
RedHat Enterprise Linux
Ubuntu
DistroWatch.com

VirtualBox and Virtual Disk Images

VirtualBox
http://www.virtualboximages.com
How to install VirtualBox on Windows
How to install VirtualBox on Mac

RAR Tools

Windows:
7-zip
Free WinUnRar

Mac:
UnRarX
iZip