is there any way to make IIS language as English? my OS is currently in Turkish so the IIS is.
My OS is windows vista home premium so AFAIK, I cannot change the language of it.
You must set English as the display language in the OS. You can do that in the Control Panel -> Region And Language -> Keyboards and Languages -> Display language (at least that is what it is in English.). Vista Ultimate will let you add any language pack for free. The other versions probably require a small payment for each additional language.