Then I would definately recommend SUSE - they have among the best manuals.
However, Linux is one OS which you preferrably want to have someone to talk to locally, if something goes wrong or just not as you want.
It's quite command-prompt dependant, so I hope you're not afraid of typing & will miss those GUI's (though X-windows alleviates that somewhat).
Hrm ... better then to maybe start playing with Linux on a small system, where if something goes wrong nothing bad will happen. A server as "testing ground" is never a good idea, if you don't mind me giving you this counsel.
Get used to Linux first - only once you are confident with yourself, you should move on to the server ... hope this makes sense. I don't want you to be "prodding in the dark" without a clue as to where to go. Linux can be quite scary in the beginning to some ppl ... esp. if it's their "first time".
Hope this helps somewhat

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