Inactive File dropdown menu

Click the cursor on File and the dropdown menu is an inactive list - no highlighting, no activity. But use ALT-f and the same list opens with New highlighted and active and the up/down keys move the highlighting bar and render all the other choices active in turn. I've clean-uninstalled Office 2003 and deleted Normal.dot and then reinstalled from the original disks but the problem persists (with a new Normal.dot). All the other dropdown menus work normally and Excel and Outlook are normal except when using Outlook for a New mail