I think I like Jamesc359's better, but I had a try at it too (can't get better unless you try, right?) So I used some tips that I've seen elsewhere about cloning and healing things. Actually, almost all my fixes were just using the spot healing brush in different ways.
Like I said, I used the spot healing brush, but first I duplicated it to a new layer and ran the Dust & Noise filter at 1px to get rid of some of the major stuff. Then I set that to darken since most of the big scratches were light and by using this filter it softened things up quite a bit. Then I did a high pass filter for sharpening and set the opacity to about 60% to bring out some of the detail. Now the rest was done just using the spot healing brush set either to darken (on light areas), lighten (on dark areas), or normal. I learned that trick because it helps make sure that you only effect the area that you're meaning to. So yeah, lots of spot healing on separate layers.
