Word 2000 tool bars disapeared

We recently have had 2 different computers operating under windows 98 and running Office 2000, lose their tool bars and file menu's in Word. Excel and Outlook tool bars and file menu's are unchanged. I've tried deleting and re-installing office 2000including deleting the office 2000 folder and the problem remained, which means that the problem is either in the registry or in a DLL in the system directory. Does anyone know how to restore the tool bars and file menu's in Word 2000, or know wherethe tool bars and menu's are stored? I have done a virus check and there no virus's on either computer. By the way the 2 computers exibited this problem about 1 month apart. It is possible it was caused by operator error, although I'm not sure how one makes the file menu disapear.