Giving the right "OwnTicket" to the unprivileged group

Hello everyone,

I’m using RT 4.2, and I have two question?

The first question : Please, is it possible that a user can own tickets
knowing that he belongs to the group unprivileged and I give the right
"OwnTicket" to the group unprivileged.
My problem: when i would like to chose this user in a ticket I don’t find
it in the list box of owners.
The second question: when I’m logging with this unprivileged user in the
self-service UI, I can watch other’s tickets even if I’m not the owner,
please is there a solution where the unprivileged user can see just tickets
where he is the owner.

please help me I’m blocked in my project;

Thanks a lot, yours sincerely.