To unzip require that your OS has the ability to unzip those files. Windows update is outside the scope of Firefox browser end-user help here. Did you check the Windows accessibility features to insure the fonts are the correct size so you can read and also check your "screen resolution" that they are "Native resolution" for viewing as along with update Video drivers. And check Firefox accessibility features to insure they are set for correct viewing as well. https://support.mozilla.org/en-US/kb/accessibility-features-firefox