Quote:
Every photo scan I've done looks dead and flat.

This can be fixed in post-processing. The "auto contrast" button in Picasa and similar buttons elsewhere should do exactly what you need. If your scanner can get 16-bit output (i.e., huge TIFF files) rather than 8-bit output (i.e., compact JPEG files), the results will be significantly better because you'll have more to start with.

If your scanner cannot get 16-bit output, then crank up the scanning resolution. You can do the contrast correction and then scale the image back down to the size you want, and you'll generally still have a nice smooth histogram.