I've had a number of questions about scanning images into Microsoft Word 2007 so I asked one of my colleagues to dig into the situation.
He's confirmed that this is an area where we've changed the functionality since Word 2003. Instead, you need to scan images to your computer and then insert them into Microsoft Word.
Here are some more useful links:
- Demo: Add pictures to a Word 2007 document from a camera or scanner
- Insert scanned images in 2007 Office programs
- Scan and edit a document
Hope this helps!