Nikaah & Marriage Issues

Q: Please explain the issue of milk kinship in Islam. Also explain the fiqh and virtues.

Q: Are condoms allowed?

Q: My question is regarding nikaah. A guy performs nikaah himself (without a mufti and wali) with a girl taking Allah as his witness. The girl accepts this nikaah. He says she is now his wife. What is the ruling on this?

Q: Can I marry a hindu low caste girl if she accepts islam on her free own will?

Q: I want to know the fidya for having relations during haidh.

Q: I want to know one married lady converted her religion from Christianity to Islam and now she is separated for the last two years from her husband. After converting to Islam, is her previous marriage valid?

Q: Are the brothers and sisters of one's grandparents mahrams or not?

Q: What's an easy way of explaining the times of salaah to a class of about 10-13 year olds?

Q: Is it permissible for females to attend a nikaah at a mosque that has female facilities?

Q: When will it be waajib for a person to get married? Similarly, when will it be Sunnah for a person to get married?