To open or print DjVu files you need one of these:

DjVu browser plug-in from Lizardtech.com
DjVu Solo program
Irfanview 3.81 or later (you need the DjVu plug-in - just get them all)

Advance through pages with the > arrow (Down arrow in Irfanview). When printing from DjVu (or Acrobat for that matter...) use the program's printer icon, NOT the IE / browser PRINT command!