Control access rights of pages

Hi all,

I’m trying to utilise a wordpress module as the “help system” of my site, which is a custom-built CMS in php+mysql.

My intention is to install the wordpress under the directory /help and add page sets in the hierarchy
-Help
—-Admin pages
—-Active user pages
—-Guest pages
I’m planning to make three users apart from the “wordpress Administrator”. I need to consider the first user as Admin, who can view all these pages
The second user(Active user) can view both “Active user pages” and “Guest pages”. Where as the third one can only read the last set of pages.

I know, I can make a plugin to “auto-login to wordpress“, based on the session values in my existing system and I can control the roles of users by the “role management plugin“

Please let me know if there is something wrong with my above idea.

Now, how do I control the access rights to certain pages based on the user privileges? I don’t want to make a page private or password protected, but the user with the right privilege should get the access rights for the desired pages, and the links to those pages should be on the sidebar.

Is it possible?

Any help/suggestions would be appreciated.