Please follow this steps to disable control panel in windows xp:
1. Click Start and click Run.
2. Type gpedit.msc and click OK.
3. Within the Group Policy Editor, expand the following:
User Configuration | Administrative Settings | Control Panel.
4. In the details pane, double click Prohibit access to the Control Panel.
5. Click Enabled and click OK.
With this setting enabled, users will be unable to start the Control Panel or run any Control Panel items.It also applicable in windows 2003.