When you refer to charts you are referring to the Figures? I could not try printing because I'm out of ink. I did a print preview and it looked OK. If you do a print preview, do the defects appear in that?
I took a look at File/Properties of "Intro to Feedback". There are a number of fonts listed. Could it be that you don't have all the fonts and it's substituting incorrectly? That's a wild guess; I don't have Geneva on my PC. I did not check the fonts on the other PDFs. Mostly likely the same set but you could take a look. Edit: You could install any fonts you don't have. Geneva for instance is freeware.
Along those lines, check out this link
about printing as an image. There may be other fixes.
Edited by Nanobyte, 29 January 2013 - 04:31 PM.