White lines all over the PDFphotos!

I "printed" 5 of my Tiff images on PDFCreator. Each of the photos are about 45.8 Mo. And I've "combined" all 5 photos on one page. I've tried "printing" them in different print "quality" (ex between 150 x 150 to 720 x 720). But no matter how I do it, the outcome is too bad, because there are long white parallel lines across each photo and approximately 3 cm between each lines on the photos. The presentation of the photos are simply too bad with all the white lines on.
If somebody can tell me how the lines arise or rather how I can avoid them, I will be rather happy.

I have a PC window 7 64