if you are a total newbie, forget making a multi runtime Poser set-up. if you study this tutorial and use the Content Manager. life will be far simpler.forum.daz3d.com/viewtopic.php
for future reference, when you 'unzip' the files, don't unzip to any old where. when it asks you where to unzip the file, point it to ROOT( which disc and where you have installed DS) DazDAZ3 content if you are using Vista as your OS, DS3 will install the Content folder in Documents by default and it would probably be best to install all new content to that folder.

if you use the Content Manager, you will only need 1 runtime.
the Content Manager allows you to organise your content any way you like without moving it about on your drive