How can I prevent my users from disabling the password-protected screensaver that I configure when setting up new systems?
If your computers and user accounts are part of an Active Directory (AD) domain, you can use one Group Policy Object (GPO) to deploy a policy to all your users that prevents them from disabling the screen saver. If you don't use AD, you'll need to configure the setting in the local GPO of each computer.
Whether editing a GPO in AD or a computer's local GPO, maneuver to the User Configuration\Administrative Templates\Control Panel\Display folder in the Microsoft Management Console (MMC) Group Policy Object Editor and enable the Hide Screen Saver tab policy as shown in Figure 1, page 16. Now when users open the Display applet in Control Panel, the Screen Saver tab just won't be there for them to access. Notice that there are other policies that enable you to configure the screen saver itself as well as its timeout value and other parameters.