In your case there is no step by step to your question but we have answer and suggestions.
1. If you think you icons are to big to can go to >preferences >more preferences >file management and select your icon's view default from 100% to 25%.
2. You can configure your video settings to obtain 1280x800 resolution. Open terminal and type:
select the HARDWARE tab and click on configure under your monitor and same applies for video card.
3. Go all the way to the top of menu and select GENERIC LCD display select >lcd panel 1280x800 and use the driver and see if that helps.
4. Make sure you select correct video drivers. If you dont you may not be able to login again. Make a backup of your /etc/X11/xorg.conf before you make any changes. Now reboot.