Difference between Azaan and Iqaamah

Q: Kindly tell me what is the difference between Azaan and Iqaamah? Kindly consider this Hadith "The people mentioned the fire and the bell (they suggested those as signals to indicate the starting of prayers), and by that they mentioned the Jews and the Christians. Then Bilaal was ordered to pronounce Adhan for the prayer by saying its wordings twice, and for the Iqama (the call for the actual standing for the prayers in rows) by saying its wordings once. (Iqama is pronounced when the people are ready for the prayer). Sahi Bukhari Volume 1, Book 11, Number 577 in Azaan we saying words twice but in iqamah we saying words once as mentioned in above hadees. Kindly now tell me your answer as per Quran and Hadees.

Does one have to make qadha of the Witr Salaah if the Esha Salaah was not valid

Q: A person performed his Esha and Witr Salaah on a particular day. Later, he realized that his Esha Salaah was not valid (after the time for Esha and Witr had expired). Should he just perform the qada of Esha (since it was invalid) or should he also perform the qada of Witr (even though he performed witr correctly)?

Superstitious beliefs

Q: Is it correct to believe in things that people say like when washing a baby's clothes, one should not wring or twist it as it twists the baby's stomach or baby's should not share clothes as it might pass something on.

Receiving a good proposal

Q: A girl got a good proposal for her marriage. Everybody is satisfied with all other aspects except the boy's age, he is only one year older than the girl so, as the girls get older soon due to delivery and all, girls parents are in confusion whether to accept the proposal or not. May mufti Saheb please give your precious suggestion in this regard?

Does nikaah break through separation

Q: Is the nikaah over if a husband and a wife are separated for 2 years? One of my Muslim sisters has been married for 3 years. She hated him because when she got pregnant he told her to do abortion just four months after the marriage and he left her until she delivered the baby then he was back to her and after she forgave him they were staying in separate homes while she was taking care of her sick mom. He did zina with another woman and after two months they were back together again. Then he told her about what he did and since then she never consider him as her husband and she asked him for divorce but he never granted her divorce. He said to her since I did this mistake you can do whatever you want and I will be ready to accept you then we will be equal and she hated him even more. After one year she travelled to another country and she liked a guy which she wants to marry but she is confused if her nikaah is over or cancelled since it's been almost two years now that they are not living together and she doesn't want him but he is refusing to give her talaaq.

Quran khaani

Q: Is it right to do a Quran khaani for a person who has passed away recently? If it is wrong can you provide evidence and information as to why it is wrong for example hadeeth, etc?