I don't have any particular reason to avoid YouTube, and I've done that in the past. I just thought it would be easier to post directly on Facebook, since that's what Barbara wanted.
I was able to do exactly what I want with Windows Live Movie Maker. I uploaded a photo of Barbara, and then added her recording. But that made for a tedious video, so I added photos of flowers, punctuated by copies of my photo of Barbara. Windows Movie Maker has a button for "publish on Facebook," but that didn't seem to do anything. So, I saved the file in WMV format, and uploaded that to my Facebook page. When I've finished testing it, I'll share it on Barbara's page.
-Joe-