Re: Linux n00b needs teh helpzors!!!
For your kind of purpose, i'd suggest you to try MandrivaLinux, it's quite easy for the newcomers, (setup is quite complete after the first installation) and you have the mandriva documentation avaialble online (in the browser i mean, you just browse the local files) and/or via pdf files (also available on the free DVD).
Setting up the file sharing with windows (or other systems) can be done via the "Mandriva Control Center" (MCC) which has plenty other utilities.
Ubuntu provides the tools gnome provides, Mandriva has also them but the MCC is still a lot more advanced for usage than the tools of gnome (and kde). in Mandriva, you won't have to choose between KDE and gnome since both are provided.
Last, there are 'wizards' to set up easily many stuff (like file sharing, setting up a webserver, ...). To have them, just do : urpmi drakwizard, and that'll be all !