Restricting users from saving files…

Hi all,
I am trying to use “mmc” command through run in order to restrict users from saving files or download files from the internet. Knowing that the computers are not under any domain. They are for common use in a lobby area. I am trying not to use a third-party software. All I need is not to allow users to download files to the desktop or any other locations.

I appreciate your help…
Thanks and regards…
Khaled