Hi Dave,
All of this is possible.
As long as the users aren't granted any of the System roles (System Admin, System User) in report manager they will not see the site settings link at the top of report manager. These are administered under the Security tab in Site Settings.
Data Sources and Datasets are managed just like any other reporting folder. Click the drop down and select security. You can then remove the Browser (and any other) roles from the users or groups they are associated to.
Hope this helps.