You are right the advanced button does bring up the other screen modes. Have you tried updating the driver for your display in device manager? My information says:
Driver Provider: S3 Graphics, inc.
Driver Date: 11/7/2002
Driver Version: 6.13.10.1100
I too am use built in graphics. You might also try rolling back the driver in case some other software made changes to it.
Regards,
Xerxes