changing language

hi to all i have installed windows xp sp2 before some days. it has problem of language that the default language is arabi. i change this language to default one(english us) through regional settings but the problem is still exist i cant open sites which have unicode font and can display other languages also the contents of these sites display like ?????????? also in the desktop when i right click the next options after paste shortcut r displayed same(????). i also change the advance options to english us at regional settings. plz tell me what can i do for this problem to be resolved......