Is the marriage contract considered valid if concluded at home by the marriage official (Ma`zon)?
Yes, it is valid as long as it is registered at the court.
My father passed away, and he had life insurance with "Alico" for an amount of 12,500 dinars. He had paid premiums totaling 2,000 dinars. The insurance company paid us the insured amount. Should we take it, or is it considered forbidden (haram) money? And what should we do with it if it is forbidden?
You may take the amount your father paid to the company. The remaining amount is not yours. However, if you must take it, then accept it and donate it to the poor. And Allah Knows Best.
Is a wife considered divorced if her husband refused to go to bed with her (for sexual intercourse) for two months?
A wife doesn`t get divorced no matter for how long her husband refuses to have sex with her, and she had better go to court.
What should a person, who doubts the validity of his Wudu, or over performs it, do?
One who doubts the validity of his/her Wudu while performing it should redo it until he/she is certain of having attained purity. But, if doubt was after having performed Wudu, then he/she should not pay attention to that as doubt after the end of an act of worship does not count. This is of course in case doubt was within the reasonable limits since once it goes beyond that, it becomes a whispering of the Shaytaan (devil) which he/she should ignore as the Wudu is valid.