Mandrake has done well at making theirs the Windblows of the Linux community. Don't get me wrong, it's great for someone that does not want to know anything about their system. However, It would seem to me that we are interested in knowing something about the OS that is in use, otherwise there would be no need to purchase those heafty books that aim to teach.

For those with no inclination to know what is really going on : Mandrake
For those that are up to a challenge and would really like to lear : RH or SuSE
For those that think you know, Slackware or even one of the BSD's at this point might be well advised.