For non computer literate or the terminally impatient, Mint MATE.
For the slightly more adventurous but still ill equipped, Mint KDE.
For the literate user looking for good engineering OpenSUSE KDE.
Those would be my recommendations. They're both green.. funny co-incidence

I strongly prefer 'independent' Linux distro's rather than 'based on Ubuntu' which is in turn 'based on' Debian. Too many fingers on the code.