If the Themes Service is not running your desktop may look different in subtle ways (white taskbar, start orb missing/changed to XP style Start button, Explorer shows a tabbed display) and if you try to change the Theme you will find that none of the Themes on this page are clickable:
First make sure the Desktop Window Manager Session Manager Service is running.
Click the Start orb/button and enter "services.msc" to open the Services applet and choose to Run as administrator:
Locate the Desktop Window Manager Session Manager Service, double click it to open the Properties and and be sure the Startup type is set to Automatic and that the status is Started. Make any adjustments so it looks like the example and click the 'Start' button to Start the Service if it is not running:
Next check the Themes Service which should look like this:
Restarts VPS and all themes are activated