You can disable gmail gadgets for selected users by following these steps.

Go to your Google Apps dashboard and click on the ‘Organizations and Users’ tab. 
Under the 'Organizations and users' tab, add a new sub-organization. Here, we have called it ‘Support Group’

Go back to the list of all users and move only the selected users into the new sub-organization. You can do this by clicking the checkbox to the left of the user names, then click the 'Move To' button and choosing the new sub organization. 

Now in the ‘Services’ tab, click on ‘override this setting’, which allows to override the inherited settings. You can turn on/off the specific services that users in that sub-organization require.

Finally in the parent Organization turn off access to the sub organization to disable the gadget and quick link for all other users in your domain.

Google Apps - New Admin console

Below is the workflow for New Admin console.