If you want to hide the User Accounts in Control from those who don't need to have access to it, here's how:

1. Click Start | Run.
2. Enter gpedit.msc in the Run box to open the Group Policy Editor.
3. In the left console tree, expand User Configuration | Administrative Templates | Control Panel.
4. In the right details pane, doubleclick "Hide specified Control Panel applets."
5. Click the Enabled option.
6. Click the Show button.
7. Click the Add button.
8. In the Add field, enter nusrmgt.cpl