Yes, chef is correct. Microsoft .avi (audio/video interleave) container files can hold MPEG2, MPEG4 (XviD/DivX) or some other encodings.
However the DVDR3440H will play back DivX of certain vintage. From the Philips website:
"Plays MP3, WMA, JPEG, DivX 3.11/4.x/5.x/6
Multi-format playability allows you to play most file formats for maximum listening and viewing pleasure, including MP3, WMA, JPEG and the popular DivX digital media format. DivX playback enables you to play and share compressed high quality DivX video content beyond your computer."
@mattman190973:[/i] download GSpot and drop your .avi file on it. It will report what is inside the .avi container file.