I have been doing all of the scans without dust removal so far. The dust removal post was just an experiment. I have seen how it can destroy detail such as removing part of the number off the front of an engine. In this example it didn't seem to do any noticable damage. Apparently it doesn't do too well with scratches even though it is labeled as dust and scratch remover. Besides the possibility of losing detail it also adds quite a bit of time to the scan. It has to run a second pass with some IR light.
Thanks for the explanation on film grain.
I agree, I wish that digital cameras had been available earlier. I never really got the hang of taking a good shot on film. It probably didn't help that I used run of the mill film and cheap processing. With a digital I can take a half way decent picture. Plus I can make my own prints and adjust them the way that I like.