Ubuntu

Ubuntu is a free, open source operating system that starts with the breadth of Debian and adds regular releases (every six months), a clear focus on the user and usability (it should "Just Work", TM) and a commitment to security updates with 18 months of support for every release. Ubuntu ships with the latest Gnome release as well as a selection of server and desktop software that makes for a comfortable desktop experience off a single installation CD.

Visit website for more information: http://ubuntulinux.org/