Prints fade over time, and lose certain colours. I scan them at 600 px/inch, which gives me 10 megapixel pictures, and something to work with. I use Gimp to process. I think the prints really are 200 dots/inch, so they come out fuzzy. I use the unsharp mask, on standard settings to really sharpen them up.
I'm mildly colour-blind, so I want an automatic process. I use the auto white balance to correct the general shift of the fade, and then I use auto colour enhance to pump up the colours. I save it all as jpg.
This is a 20 year old print of #2. I've cut it down to web resolution. If I can find my slides, I'll look at them as well.
ps. I bought a reconditioned Epson v300 from their site. It is absolutely brand new, at half the price! Those California companies probably use it for 10 minutes before they double in size, and get the monster scanners!