My husband told me that he concluded our marriage with a fake name that belongs to another person, because he was sentenced. Nowadays, he recieved an ID, passport and birth certificate with the his current name. What is the ruling on being married to him?
Praise be to Allah, The Lord of The Worlds, and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions. As regards being married to the person mentioned in your question: The marriage is valid so long as he was the same person your guardian concluded the marriage with, even if he changed his name i.e. if your marriage contract was concluded with the same person, since what counts regarding marriage is the persons not names. And Allah Knows Best.
What is the ruling on the ablution of one who washes his arms from the wrist to the elbows?
In the school of Imam al-Shafi'i (may Allah have mercy on him), washing the arms (hands) is achieved by washing the arms completely, from the fingertips to the elbows. Washing only the palms at the beginning is insufficient, as washing them at the beginning is a Sunnah, but after washing the face, it becomes obligatory (fard). The person performing ablution must wash his palms along with the arms after washing the face. If he does not wash his palms, his ablution is invalid and not correct. And Allah the Almighty knows best.
Is it permissible for a financially capable woman to pay the Zakat to her sons or one of them?
It is permissible for a mother to give her children from zakat if they are eligible to receive it, even though she is obligated to provide for them. This is based on the saying of the Prophet Muhammad (PBUH) regarding Zainab, the wife of Abdullah Ibn Mas'ud (may Allah be pleased with them): "Your husband and your children are more deserving of your charity" [Al-Bukhari]. And Allah Knows Best.
Is it permissible to offer Istikhara prayer (seeking guidance) after Witr Prayer (A confirmed Sunnah which is offered after Isha prayer and before Fajir prayer with a minimum of 3 Rak`as and a maximum of 11)?
It is permissible to offer Istikhara before and after Witr prayer as it is permissible at any time except that in which prayer is disliked. And Allah Knows Best.