I often find questions which I flag as dup, to close or other. However I have the impression that not many other had a look at them. So my question is: Is there some queue or list for non-moderations where I can find all flagged questions. This would probably help to close or mark questions which have low quality.
No, the only way (currently) to view the list of flagged questions is to either be a ♦Moderator, or have 10,000+ rep. If you have that much rep, you're virtually a moderator already. As the FAQ put it,
At the high end of this reputation spectrum there is little difference between users with high reputation and ♦ moderators. That is very much intentional. We don’t run Ask Ubuntu - Stack Exchange. The community does.
So, for your average user, the list of flagged questions is completely off-limits. You can only view it once you have obtained enough rep to officially moderate the questions.
I am in hearty support of your idea - normal users being able to view the flagged questions list. Not at 1 rep, though... 250 might be appropriate. (200 is when you can see the Review queue.)