My little postcard camera (canon powershot a70) is getting old... a couple times now, the lens goes wonkie (that's the technical term I found on the internet) and instead of an image on the screen, there's lots of horizontal lines. The standard Marine Corps technique usually works to fix it (thump it a couple times) but I think all this Field Maintenance is making my pictures a little worse. Here is the Histogram for one of my recent potraits... I don't know if there's enough information in this image, but I don't think the little white chasms in the regularly smooth curve are good things.

Couple questions:

1. Is my interpretation of the histogram correct?
2. What other information do y'all need to tell if my camera needs work/replacing?
3. Is there anything I can do about the images I've already taken? (In photoshop...?)
4. Anyone willing to part with a Rebel for cheap? =)

Thanks for the help and advice...

C