Maybe this was covered somewhere else, but in the latest June 2003 issue of Macworld magazine, the tip of the month is how to turn off the Ken Burns affect..resetting imovie to only put in the affect if you want to hit APPLY, rather than as a default.
Using TextEdit, open the com.apple.iMovie3.plist file, found by following this path:
-/Library/Preferences/com.apple.iMovie3.plist
Find the autoApplyPanZoomToImportedStills entry. It is maybe half way thru the document. Two lines below this entry (and one line above <key>Option autoSceneDetect: %d) you'll see true . Change this to false . Save and close the file, and imovie will no longer pan and zoom as default on your photos...only when you want them.
Thanks to Macworld and Karl H. Hehr of Ames Iowa for this!