Answer
(Fatwa: 1884/1315/L=1432)
(1) One should have the consent of children for their marriage as well. Marriage against the consent of children often cause trouble.
(2) If one does not find such a fault in one’s wife which makes talaq inevitable then it is not necessary or wajib to give talaq on parents’ demand. Also their demand for talaq is not right as well. However if you divorce your wife in order to please your parents then it is permissible.
(3) You should try to make your parents happy by putting some influential person in this matter and if nothing works and he is not agree in any way then you should give one talaq to your wife. And later if your father is happy and allows you to keep that second wife again then you can do rajah if iddah is not over and after iddah you can perform fresh nikah.
(4) There is no fault of second wife. But this is your fault that you married second time without the permission of your parents.
(5) Its solution is the same as written under the question no 3.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband