From Default Picture Settings :
If you have a need to format quite a
few pictures using the same settings,
the easiest approach is to create a
quick-and-dirty macro to apply the
formatting settings you want. You
could then paste the picture, select
it, and then run the macro. You can
create such a macro by following these
general steps:
Paste the picture in your document.
Select the picture you just pasted.
Start the macro recorder.
Make the size and position changes to the picture, as desired.
Stop the macro recorder.
Your macro is now ready to use.
Whenever a new picture is pasted in
your document, select it and run the
macro to apply the "default" settings.
See also Assigning Shortcuts to Macros in Word 2007 :
If you really want to get the most out
of your commonly used macros in
Microsoft Word 2007, you can assign
buttons or keyboard shortcuts to them
so that the process of running these
macros is even more efficient.