Rights of Admin, Contributor etc

Hi,

I was wondering if it’s possible to give different rights to certain members? I want them to be customizable, also.

So one user logs in, no settings to change, can only post, and only has the choice of say 2 categories to put their post in and to possibly tag the post.

Is this possible in the standard admin panel, or am I looking at a plugin, or a custom admin panel?

Thanks,
James