This is a simple little program that make the Blizzard Warcraft III to fit your current screen resolution. Will you can do this by using the regedit yourself to modify the key: "HKEY_CURRENT_USER\Software\Blizzard Entertainment\Warcraft III\Video\" but this tool is much easier.
The program is in Chinese and I don't want to change it but you can still pretty easy to use it since you only need to push one button(with the [确定更改] sign) once. If you really wanna use other language, please download the source code here: https://github.com/zhujunsan/Warcraft-III-Resolution-Changer
The program itself is at HERE.