بسم الله الرحمن الرحيم
(Fatwa: 1104/878/D=11/1436)
It is necessary to pass the iddah of four months and ten days for a woman whose husband dies. It is a clear order of the Holy Quran. It is one of the rights of Allah. It has nothing to do with the woman either she is too old or menopause. The period of iddah shall be counted from the day on which the husband died. It is forbidden for such woman to go anywhere during this period. Also she is forbidden to wear elegant clothes and jewelleries (bangles etc.). She shall spend these days in mourning.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband