*HAH*!! I have had a moment of Great Triumph over the evil that is Word! I have figured out how to make its default setting (normal) automagically double-spaced! I’ve been trying to figure this out for YEAAAAAAARS. Today, in a fit of something or other, I actually looked at the help files. :)
I know you’re all dying to know how to do this, so I’m going to tell you. Go into Format. Choose Style. Highlight Normal. Click Modify. Click Format. Choose Paragraph. Choose Double under line spacing. Click OK. Check Add to template. Click ok. Click Apply, then close.