The problem is that most modern printer drivers reset all print job related settings to factory defaults at the start of the print job in order to achieve a known state, and then build up all the user-specified settings from the ground up. So any job-related settings can and usually will be overridden by the settings in the printer driver.
The standard solution is to make one computer act as a print server. Have it share the printer to the other systems on the network, and specify the defaults you want at the print server. When the clients connect to the print server, they will either automatically receive the correct printer driver and the defaults as specified by the print server administrator (the Windows way), or they'll submit the jobs to the print server in some standard format (usually PCL, PostScript or PDF) and the driver at the print server will handle the job options and any post-processing required, applying any settings configured by the print server administrator whenever appropriate (the Mac/Linux/Unix way).
If your users connect directly to the printer itself, there is not much you can do: the users' default settings will be whatever they have specified when creating the printer queue (connecting to the printer). You might supply the users with instructions to make some specific settings when connecting to the printer, but the users will be free to disregard those instructions... unless you can go to full lockdown on the users' computers, allowing only administrators and/or help desk workers to install any printers.
If you mentioned the operating system version(s) your users are running, it would be easier to give you more specific answers.