Monitor woes!!

When I turned my computer on this morning, there was a message: “display adapter type or current settings do not work with your hardware:. My icons are large and my display settings are 16 color 640×480 pixels. I used to have a 32 bit hi color option in settings but it is not there. I have tried to reset it to 16 bit hi color or 256 color but when it reboots it goes to a DOS screen that says” Windows is restarting” after a few minutes, it says ” windows protection error press any key”, then it says after pressing a key: “It is now safe to shut down your computer”. Then I try again and get same results; etc etc etc.

Help! Windows 98se