Display screen resolutions change when I shut down and start up again.

[Billi]

Every time I start up my computer, (running Windows XP Home edition) after a minute my screen resolution changes to the lowest setting. My slider has only three settings. I click apply, the screen goes black for a few seconds, screen returns and I click OK. Problem solved? NO. I go through this "fix" every time I shut down my computer and turn it back on. Could my Monitor be the source of the problem?
Please help,
Billi

 

[CompGee]

In the Start menu, type msconfig and hit Enter. In the Boot tab, uncheck Base Video and exit and reboot.