You will not gain much space uninstalling this screensaver because this is a small one. I suggest you to run the Disk Cleanup tool in order to free up your disk space. You can check the Microsoft support page to learn how to use it.
To uninstall the screensaver you can follow the steps below:
If you use Windows XP or bellow you can go to Start > Control Panel > Add or Remove Programs. In the Currently installed programs box, click on the screensaver and then click Remove.
If you have Windows Vista or above you need to go to Start > Control Panel > Programs > Programs and Features. Select the screensaver and click on Uninstall.
Also you can try using Revo Uninstaller. Even if it can't uninstall the application normally, it will force it to uninstall by wiping out all traces of its presence from the system.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.