Here is a link to a little program that switches the resolution between 1920x1080 and 1024x768 with an ALT + B keyboard shortcut. To exit out of the program use ALT + X or right click the system tray icon and select exit from the menu.
Once downloaded, just double click the file to run the program.
Resolution Switcher 1920x1080 to 1024x768
If you don't like the resolutions I can change them.
Actually, trying it out again for myself, it looks better if the 1920x1080 resolution has the same height as the 1024x768 resolution, so 768 pixels high for both.
Here's another one for that different resolution, made the width a bit less too...
Resolution Switcher 1820x768 to 1024x768
Same shortcuts, but don't run both switchers together.