Is the aforementioned commercial dealing considered haram, and what is the optimal course of action for settling accumulated debts, and is it permissible to sell the available plot of land for this purpose despite the family's and wife's objections?

To determine the ruling on financial dealings between you and those whose money you took for trade, the nature of the transaction must be defined: - If it was a valid Mudarabah (definition) (profit-sharing partnership) with a known percentage of the profit, then it is permissible. - If it was a loan, then any increase is forbidden usury (riba), and you must return only the principal amount. - If it was a Mudarabah based on a percentage of the capital, not the profit, then it is forbidden. In this case, all profit belongs to the capital owners, and you are entitled to a fair wage (ujrat al-mithl). Any loss is borne by the capital owners, unless there was transgression or negligence on your part.

As for selling the land to repay debts, you must sell it if you cannot repay them except by doing so, and no one has the right to prevent you from selling it, unless this land is your sole source of livelihood and that of your dependents. In that case, you are not obligated to sell it. A bankrupt person is allowed to keep what is necessary for their livelihood and trade, and the remainder is sold.