Was Microsoft Office 2003 first one?

No. There was Office 2000, Office 97 and Office 95, Office 4.x, Office 3.0 and before that it was just Microsoft Office, launched in 1989.
No. There was Office 2000, Office 97 and Office 95, Office 4.x, Office 3.0 and before that it was just Microsoft Office, launched in 1989.