Conditions for the validity of Nikaah

Q: If a man and a woman plan to get married just to satisfy their sexual need. Further more they have decided to get separated by divorce afterwards. Are they committing a sin?

Q: Is it better to mention the full name of a newly convert non Muslim in his nikaah in the audience even though he has got a non Muslim surname (family name) or one just has to mention his normal Muslim name (Yusuf or Ahmad etc) and leave out his surname?

Q: I married a Christian girl and conducted the Nikah myself - i.e. I got two non-Muslim witnesses, asked her if she accepted my proposal based on the Mahr I gave her, she accepted and I then read the Nikah Khutbah, and confirmed that I have accepted her as well in my Nikaah. First Question: Is my Nikaah Valid? Secondly - things did not work out and I have subsequently given her 3 Talaaqs telling her that I divorce her in front of two Muslim male witnesses. If she reverts from Christianity - can I remarry her (perform Nikah again) or not? (Does she first need to remarry someone else etc.)

Q: The girl I like was non Muslim. Now she is a Muslim. We both like each other for 4 years. Her parents are not Muslim they don't agree to the marriage and they dislike that she became a Muslim. Does she require her parents permission for marriage?

Q: If a man is to get married but his parents don't agree with the marriage. Is it halal to publicise and go ahead with the marriage without their approval?

Q: I had a question about marrying a second wife? I told my wife I wanted to marry another wife and she said I would need to divorce her first? She would not accept that second marriage! What is the ruling on this?

Q: I am a sixteen year old boy. Can I perform nikaah to a sixteen year old girl?

Q: I loved a girl since one year and she also loves me but the problem is that she is of Hindu religion and I want to make nikaah to her. Can I do so without the interference of her parents?

Q: I would like to know is it permissible that on a daughter's nikaah, her father and brother may be the witness (Gawah)?