Making a dual monitor setting in Kcontrol endure

Yet another computer in the house having died, I have temporarily set my husband up using my netbook with a monitor, keyboard and mouse, running Squeeze with Trinity 3.10.13.1. A single screen is set up that displays on both monitors the same. This is unusable on the monitor. I can find no way of setting two different settings. The screen number control is greyed out. So I use KContriol to set up a better resolution and sync rate, which necessarily sets itself up on both. Except that the netbook screen goes on strike and goes blank. This suits me fine! But, although I have set this up in KControl, every time my husband reboots, I have to set the monitor up for him again. He is forgetting even those computer skills that I had managed to teach him. I haven't a hope of teaching him how to use KControl for himself. Help! When I have finished the course I am doing, I shall set him up properly. But that is not until December. I need to limp him through now. So is there any way I can persuade Trinity to keep the settings in KControl?? Thanks, Lisi