There are two ways to turn it off using the graphical interface :
At Farm Level :
- Go to Central Administration > System Settings > Manage Farm Features.
- Look for Social Tags and Note Board Ribbon Controls and Deactivate it.
Farm Level deactivation of tags and notes
Ae User Group Level :
- Go to Central Administration > Manage Profile Service: > User Profile Service Application > People
- Click on Manage User Permissions and you will see a screen similar as below :
Permission for User Profile Service Application
- Here you can disable Use Social Features to turn off Tags and Notes for that particular user, group or type. As you can see here personal Feature, Personal Site and Social feature are three different things here