There is a know problem with Acrobat 7 plugin that prevents Word 2003 from saving normal.dot template.
See references like
Microsoft Knowledge Base Article ID 906899 - Word does not save changes or you receive an error message in an Office program after you install Adobe Acrobat 7.0
or the article "Lose that Adobe Acrobat Toolbar - without losing the Adobe functionality"
If you don't want to use regedit to change
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Word\Addins\PDFMaker.OfficeAddin]'s subkey "LoadBehavior" from 3 to 0.
you can use these at your own risk.
Registry patch files (.reg) to toggle Acrobat 7 plugin on and off (right click to download, otherwise your browser may just show you the content of the files)