To change your screen resolution
1. Right click on main desktop 1. Open Display in Control Panel.
2. Select Properties option. 2. On the Settings tab, under Screen resolution , drag the slider, and then click Apply .
3. Choose Settings.
4. Change Screen resolution in 1024 by 768 pixels. 3. When prompted to apply the settings, click OK . Your screen will turn black for a moment.

4.Once your screen resolution changes, you have 15 seconds to confirm the change. Click Yes to confirm the change; click No or do nothing to revert to your previous setting.

For Windows XP
5. And then Apply.