Arnulf:
It is almost not possible to avoid some scratches on the films, even before you scan it. The scratches can be generated by the camera itself, by film developing, or by photofinishing to the prints. That is why Digital ICE is such an important feature on a scanner. If you suspect a scanner will scratch the films, which rarely is the case, you should examine the films themselves before and after the scans, but not the prints. Modern photo-printing machines have the function similar to Digital ICE, so they can edit out the scratches. By the same token, when you scan the films, since the scratches are most likely already be there, you should always turn on Digital ICE to edit out the scratches for your scanned images. 🙂