I'd like your advice on this, my case:

I want to make an international portal for students. The mainsite http://www.site.com will be international and the subdomains will be national (e.g. dutch.site.com). You only have to log in once, for space I'd rather have one XOOPS installation, but modules don't have to be shared (database).

What is the best way to do this. I mean, I know the diff possibilities, but what would you choose.

Thanks in advance for your opinion.

I suggest you to install the Subsite/multisite module (you must register for download).

This will allow you to install as much as you want subsites and share the user database (or whatever needed module).

Each and every sites have their own language and content.

Thank you for your answer. But - correct me if I'm wrong - this means I have to install lots of instances of XOOPS with one Userdatabase. Is that the only option? Because I'd rather have one (because of the space every Xoops-install takes) Xoopsinstall.