Is it permissible for the wife to give the Zakah (obligatory charity) of her money to her poor husband?
Yes, it is permissible for the wife to give from the Zakah of her money to her poor husband. And Allah Knows Best.
Which is better for a traveler: fasting or breaking the fast?
Fasting is better, unless it causes hardship—in that case, breaking the fast is better.
What is the Islamic ruling on breaking the bones of the 'aqīqah?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
It is Sunnah not to break the bones of the 'aqīqah. Rather, each bone should be separated at its joint — as a good omen and expression of hope for the soundness and wholeness of the newborn's limbs. However, if one does break the bones, it is not considered disliked (makrūh) — it is simply regarded as contrary to what is preferable (khilāf al-awlā). And Allah Almighty knows best.
If a father stops his daughter from getting married, is it permissible for her to conclude the marriage contract herself?
It is permissible for the father to stop his daughter from getting married if there was a lawful reason for that, and she isn`t allowed to conclude the marriage contract without her guardian. However, if her father denied her right in getting married for an unlawful reason, then she should go to court.