I would suggest Trustix Secure Linux, it has some neat documentation on its website and a good mailing list where people can help you set it up, it is also damn small, has fuck all services on by default (postfix, and thats about it, you even need to turn on SSH manually).
It is easy to administer and manage because it is based on Red-Hat however it is VERY minimal. It also has swup which allows you to install packages easily, its a great distribution. You can install Window Managers, X, xfce, xine, mplayer, xmms, whatever later on.