Apple's QuickTime Pro (for Mac and Windows -- $30) can be a good tool for simple digital storytelling. The graphics in this QuickTime was created using the Appleworks Draw program, which used to ship for free with iMacs and iBooks. These days I would use OpenOffice Draw program, which is free.
I could have created this using Powerbullet an excellent free program for Windows that creates Flash slideshows. Audio can be recorded in Audacity and compressed into MP3 format using iTunes.
Some instructions I wrote a few years ago about QuickTime Pro can be found in this pdf file. Note - I no longer have a dotmac account.