What are the rulings for the zakat on money saved for years, specifically: Is the price of gold at the time the nisab was reached considered, or the current price? And is the zakat paid in the country of residence or the country of origin, and is it permissible to give it at its current value despite the change in the value of the money? And is it permissible to give zakat to an unemployed brother, and is what was previously spent to help family members counted as zakat?

Zakat (definition) for past years is calculated based on the nisab (definition) (minimum threshold) for each of those years. If the money reached the nisab and a full hawl (lunar year) passed over it, then zakat of 2.5% becomes obligatory. If it did not reach the nisab, then no zakat is due on it. Zakat is disbursed as a debt upon you, for the principle in settling debts is "like for like," not by value. You cannot count what you spent on your brothers as zakat unless you intended it as such at the time of expenditure. It is permissible to give zakat to a poor brother, provided that his maintenance is not obligatory upon you (for example, if you are his heir and he is poor, and you have surplus beyond your own expenses). Zakat is to be disbursed in the country where the money is located.