Hello,
The dotnetnuke topic is usually a good place to make posts, so I've posted the question in here for you.
If you are creating 2 spearate websites, I would keep them as 2 separate DNN installations because if you have problems with one site, the other will not be affected.
I have gone into this in detail in:
Issue 17 – DotNetNuke PortalsHave a read of:
Portal Considerations (When to use Multiple Portals / Parent / Child or create a new DotNetNuke installation)
For 2 separate installations, yes you will have to install DNN twice and you will have to install the modules and skins twice. - I have however discussed this method:
Configuring DotNetNuke before installation
(How to create a portal site template for the wizard)
which will help to speed up the process
Thanks,