Hey guys!
Hey!
I'm kind of new to the web building world. I'm working on a new website of mine.
The site will include several tutorials, both written and video, a forum, possible chat, and a file exchange (similar to this one http://www.simv...net/svex.php).

Anyways, I've started looking for such scripts under PHP Nuke and PostNuke but am a little overwhelmed by the large database of modules. I started searching but am not sure where to find it all.

Are there any scripts which allow me to do the following and would someone mind mentioning their names?

1. Create a site which can be viewed by anyone unregistered. However in order to download from the exchange, post on the forums, enter chat or download video tutorials (not hosted on the exchange but from an external link) the user must be registered into the site (not just the forums).

2. Create a file exchange (similar to the one posted) with sections for different files in which registered members can freely upload files to the server.

3. Limit video download link (hosted on rapidshare) to registered users and some videos to members who paid for the download.

Thanks!

Here's my answers to your questions:
1. You can always set in your (Site Admin Menu) for all your site contents (blocks, modules, etc...) to be visible to all & not just for registered users. As for your Forum, you can set your Forum settings (under Modules Admin Menu) by setting permissions on it either making it Public, Registered, Registered (Hiden), Private, Private (Hiden), Moderators, Moderators (Hiden). You can also create (User Groups) to have particular access to a particular block.
2. You can also set permissions for your Download module similar to the permissions mentioned above depending upon what kind of Download module you're using (ex. NSN Downloads). Uploading is allowed depending on how you set permissions on your Download module. It's for you to review & accept the file as site admin. There's a hack that you can find in the net that makes your Downloads visible to all yet only a particular someone with the right permission will be able download.
3. You need to have a subscription module if you want limited access to your Downloads for Subscribers. Most popular subscription module is Western Studios' Subscription module version 2.0. To get this, you have to subscribe at Western Studios - Free and custom PHP Nuke themes, graphics designs, tutorials or get the free version 1.0. There's also a hack out in the net for you to set limits on how many dowloads a registered user can download in a day or week. You have this option in WS Subscription module 2.0.