What is the torment of the grave?
We seek refuge in Allah from the torment of the grave. The important point is that the cause of the torment of the grave is disbelief or committing sins without repentance. It affects the soul, and the body is impacted by it, even if we do not see it. And Allah Knows Best.
Is it permissible for a mother to stop her daughter from marrying a respectable, God-fearing young man because he isn't college/university graduate?
It is impermissible to deny a woman her right in getting married except for a lawful reason, and problems can be solved through dialogue. However, she can file a suit in order for the judge to have a say in that regard.
Is it permissible to pay the Fitr Zakah (obligatory charity) of Ramadan on behalf of a dead person?
The Fitr Zakah of Ramadhaan isn`t due on one who had passed away before the sunset of the last day of Ramadan. And Allah Knows Best.
After I was ran over, I had cracked ribs, concussion, a tension pneumothorax, and retired as a result. What is the amount of the Diya?
All praise is due to Allah the Lord of the worlds. May the blessings of Allah be upon our Master and Prophet Muḥammad and his pure progeny.
What you have mentioned requires a detailed medical report since the benefit of every organ that you have lost deserves a full Diya (In Islamic law, Diya is the financial compensation paid to the victim or heirs of a victim in the cases of accidental murder, bodily harm or property damage). Moreover, the decrease in the benefit of some organs has to be assessed by expert doctors and allocated a percentage from the Diya accordingly. Therefore, we advise you to refer the matter to the courts or reconcile with the driver and forgive him so that Allah may forgive you. And Allah The Almighty Knows Best.