If you are looking for a free screensavers manager and randomizer have a look at ScreenSaver Commander.
Nevertheless, this problem is easily solved. The
ScreenSaver Commander will fill lacks of standard Windows screensaver
option. Using this software you will be able to manage your
screensavers, and run them in which-ever order you wish. So, you can
enjoy not only one screen-saver, but all collection!
The
program gives you much more functions to control screensavers than the
standard Control Panel applet allows. You will be able to change
time-out in hours and seconds, prevent starting a screen-saver if
specified applications running, minimize all windows and so on.