Producer would work for this, Maggie, and yes, it would be better than
PPT at synching.
If you're using Windows XP, you might also check into Movie Maker. (Free
download from MS.) It would also work well -- good transitions and pans
and things in that.
You should be able to run either of these on an LCD projector pretty
much as you would PPT. Just plug in and hook up the projector, then fire
up either the Producer file via your browser or the Movie Maker file via
Windows Media Player.
PPT will, of course, work for this as well. But if you want the comments
synched, go with Producer (as was your first instinct).