Creation of content in an area is controlled by the Content Contibutor permission.
This means that you can stop people from creating content in an area, simply by not assigning the security role, but you can’t pick and choose which types of content they can create.
The exception to this rule is Processes and Questions and Answers, as they have their own permissions for each area.
If a user does not have the Content Contributor security role in any area, then the only content they'd be able to create would be their own personal blog posts.