(Written for PSP 7 and earlier, but I believe 8 and 9 are similar)
Obviously, the number one tip is: NEVER EVER work on your original scan. ALWAYS make a duplicate (Window > Duplicate or Shift +D). Close the original file and work ONLY on your duplicate. This way, you are in much less danger of overwriting your original. Why is this important? Well, say for example that you only had one opportunity to scan the only known photo of your great great grandparents. The original photo was then mailed back to Great Aunt Suzy Q hundreds of miles away, who has since died and nobody knows where her collection of old family photos has gotten to. This is also a good reason to make sure that you keep at least two backups, on separate CD-ROMs, of important photo files.
These tips assume that your monitor has been calibrated (Jasc's website has instructions on how to calibrate your monitor).
As you can see, there are only a few tutorials currently active and available. I hope to eventually be able to add more, but finding the time is not as easy as I'd like. :)
These tutorials use the photo of Mrs. Bishop from the Miscellaneous Individuals from Ohio page of my "Antique Store People" section. For best results, use this .png file (837k). If that's a little too large for your connection to download in a decent amount of time, you can use this .jpg (38k) file, but be aware that enhancing the photo will also "enhance" all the JPG compression artifacts.
Note that these techniques are for photos that are faded evenly. For photos that are faded in splotches, either use these techniques with a feathered selection or use masks or adjustment layers (more advanced techniques that I may deal with in another tutorial).
The method most recommended by experts is the use of a Curves adjustment layer. Unfortunately, this also seems to be the method with the steepest learning curve. When (if?) I ever get the hang of using Curves, I'll upload a tutorial. In the meantime, the three techniques below work very well.
PSP 7 and later versions come with an excellent tool for fixing red-eye. These other methods are offered for users with older versions of the program or who just want to try a different way of doing this. I was not able to find any old photos of my own that had enough red-eye to be useful for these tutorials, so I used a tutorial image that came with PSP 7. That image belongs to Jasc, so it is not posted here for downloading.
These methods are intended for use only with RED eyes - they may or may not work with animal eyes that glow other colors (like the dog in the PSP 7 tutorial image). I have tested the dog image with the "layer blend mode" method and that one does seem to work fairly well.
Don't forget that in PSP 5 and later, if you make a selection and it doesn't line up with the eye correctly, you can always select the Mover Tool 
, hold down the Ctrl key, and drag with the right mouse button to reposition the selection.
