I would recommend that you do this on database.
Have a look at my Research Log database preset on http://moodle.org/mod/data/view.php?id=7303 Any of the presets can be uploaded and modified to suit your local preferences. This one could be modified to display images or include files.
Feedback from our students is that this works quite well (for those that use it :-~ ). I guess an enhancement for this type of tool would be that when a user selects the entry type (diary/log/reflection) the database was able to offer a different screen format.
Paul