Please see the following information for display resolutions:
Also, you can see the native resolution for your Samsung SyncMaster here:
Thanks for responding.
I had already been through the Display Resolutions Frequently Asked Questions (FAQ), and many other resources, before I posted my question.
This is not an instance of a user that doesn't know how to set a machine up or customise it. The system is clearly malfunctioning; I am looking for someone that has seen this particular malfunction before and knows how to fix it.