Microsoft Word / Office 2007 Files Incompatible

I've had some problems at the desk lately with students and Word docs. They open their docs from emails or a flash drive and they get a file that looks like junk (filled with weird syntax and not their flowing prose). The problem: they have Microsoft Office 2007 (bundled with Windows Vista) at home and the new Word files are not backward compatible with the older versions of Office (2003, 2002, etc). The new Word files have the extension .docx instead of .doc.

I've been sending them up to BCTC on the 6th floor, where they are able to convert the files to the old format. When you create files in Word 2007, you do have the ability to save them in the old format, but of course the default is the new format.