First you should ask yourself: are the images ok for children.
If so, the problem is mostly the text. I guess you have too many words in it that may be "offensive". In my experience there is a "critical border" - if you have too many of those words all of your images are filtered out.
Concrete: check your site for "offensive words" - like this:
"site:yoursite.tld xword". eg. sex, sexy, hot, #*$!, naked etc (I don't want to destroy the trust of this forum ;-) )
Delete all these words.
When your text is clean (and of course your images) you should ask Susan in this "Webmasterheld-Thread":
If your site is clean it will be automatically reindexed in the "moderate imagesearch". But this process takes about 6 - 9 months (in my experience). If you ask Susan directly it takes about 7 - 14 days.