No it is not.
Property Taxes are taxes paid on property owned. In the state of Oregon Property taxes pay for schools and many other public services. The tax is based on an apraised value of the property. Oregon has a high property tax rate but are still one of the few states without a sales tax.
No, it is not illegal to spread human ashes in Oregon. A property owner could sue you if you do not ask permission to spread the human ashes on their property though.
It was because of her husband's failing health
Being in Oregon doesn't change the answer. The assumption is that the wife inherits at least half, if not all, of the husband's assets. But the estate has to liquidate all assets before they can transfer them to the spouse. One way or another, the spouse ends up paying the debt. The spouse has some right in all real property owned by the husband. If the assets are not enough to cover the debt, the real property may have a lien placed against it to cover those debts.
I'm certain that you can find an Oregon attorney who will be happy to fulfill this function for you . . . for a fee.
A minor cannot legally own property. Property can be held in trust for the minor until they reach the age of majority, usually 18.
You file it in the Circuit Court of the County where the property is.