Short answers, pulled from the story.
Prince Mu'izz-ud-din entered the world on the 10th of May 1661 within the Deccan Subah. His father was Prince Mu'azzam, who later became Emperor Bahadur Shah I, and his mother Nizam Bai came from a noble family in Hyderabad.
Jahandar Shah won the war of succession through an alliance engineered by Zulfiqar Khan rather than battlefield strength alone. He defeated rival Azim-us-Shan and killed him during the fighting before emerging as the victor of the struggle.
Zulfiqar Khan assumed the post of wazir upon the new emperor's rise and held absolute control over the empire. This marked the first time absolute authority came from outside the dynasty while the emperor remained figurehead.
Farrukhsiyar assembled a rebel army with support from the Sayyid brothers Husain Ali Khan and Abdullah Khan. The underpaid imperial army faced them near Agra in early 1713 and suffered defeat resulting in the end of Jahandar Shah rule.
The bodies of defeated princes rotted in the open for several days before entombment following the conflict. This treatment contrasted sharply with how previous emperors insisted on proper burials for their enemies.