如果是Win 7 Ultimate, dajian的link就可以,如果不是的话,下面的方法比较麻烦但是可行:
-download the language pack for Windows 7(google)
-run command prompt as administrator
-type "dism /online /add-package /packagepath:driveletter\dir\lp.cab" (without quotes, replace the red text with the actual path of the Chinese language pack)
-in regedit delete key \HKLM\SYSTEM\CurrentControlSet\Control\MUI UILanguage\eu-us
-reboot