You can create a new default template, with your preferred font colour:
1. Open a new workbook.
2. Choose Format>Style
3. From the dropdown, choose Normal
4. Click Modify, and select a font colour
6. Click OK, click OK
5. Choose File>Save As
6. From the Save As Type dropdown, choose Template (*.xlt)
7. Name the File "Book.xlt"
8. Save it in the XLStart folder
(you can search for this -- in Windows XP it may be in
C:\Documents and Settings\UserName\Application Data\Microsoft\Excel)
When you click the New button on the toolbar, the new workbook will be
based on this template.