I use the Microsoft shared toolkit on a classroom lab of 36 computers.
Along with a laundry list of custom settings the desktop, toolbars,
printer selection, etc.. I also preset the volume control. The shared
toolkit then is set to discard all changes that a user makes when the
user logs off or the machine is restarted. I then use a tool called
intelliadmin that allows me to remotely restart all the machines in
masse after each class. When the next class arrives, the volume is
perfect again. The MS shared toolkit can be huge frustrating pain in
the neck to configure, and is loaded with installation hassles and
setup gotchas that can suck the very life and soul out of you. Even
trying to uninstall this thing can and often does goes wrong. See their
support forums for lots more examples. If you try this, try it on ONE
machine, see if you can get it working the way you want, then run it
for a week in the lab. Then gradually image more machines as you see
fit. Otherwise, take a look at the commercial product Deep Freez from
faronics. In my experience, this product does what they say it will do
and it installs and configures within minutes.