are you trying to unzip the .ttf file?
you shouldn't, you can't. You can unzip .zip file(s) and you have to install a .ttf. Install by placing the .ttf file(s) in C:\Windows\Fonts folder.
the .zip file should be smaller than .ttf so you are extracting .ttf from .zip.
what program are you using to unzip on windows? I recommend the free version from http://www.WinZip.com/
once you open up the .zip file in WinZip you can see all the .ttf and other files inside the .zip file. You can select one or more files to extract them.
let me know if that shed any light at all....
Register and/or login to access this feature.