hide close,mini,restore button in excel

Hai friends.... I have a problem.... new to vba...
I have three workbooks -MS 2007 . Namely Startup, subj, direct . All hyperlinked. I want the users of this workbooks not to use close,mini ,restore buttons and not to use close from file menu. That is I want to hide or disable them all. I want to use a button on "Startup " workbook to save and close all the workbooks. Please help me and provide me necessary coding...

Thanking you all in anticipation
cdtp

Can't be done. Sorry. Even if it could the user would still be able to close the Window using Alt+F4 or File->Exit or right-click the taskbar icon.