Hi,
A workaround for the mouse pointer moving only when clicking issue:
To fix the resolution:
At the main menu, click Configure -> Video -> User Interface and use the Resolution drop down list to select your resolution.
Make sure the Aspect Ratio option matches the aspect ratio of your resolution.
Close the config settings completely and return to the main menu.
Then open Config again, click Video and then select your resolution from the Rendering Resolution drop down list.
This should return your game back to normal resolution.
As you may not be able to read the text at the current resolution, this image will show you what you need to click: