To expand on Sirkent's third point. What you're talking about your site doing is pretty much exactly what any of the web portal scripts out there does. Check out [url]
http://maxwebportal.com/[/url] for an
ASP one, or [url]
http://www.warez.fr/nuked.
html[/url] for a
PHP one. There's others out there too. They're free, skinnable and shouldn't be hard to customize too.