Open the Control Panel, then double click on the "Display" icon. When that loads, click on the "Settings' icon. When that loads, move the screen resolution slider to something like 800 X 600 or higher. If you can't see the "Apply" button, simply press the "Enter" key. It should cause the changes to take place.
Hope this helps.
Went into display settings, an customize desk top the setting I choose won't apply, Using Windows 98.