The entire Bible is true.
Should we stone adulterers today? No, they were under the Law, we are under Grace ever since Jesus rose from the dead, provided we trust in Him.
I get the impression you are not trying to understand the issue, but only argue against it.
"Is anyone solid enough in their faith to answer a very simple question?"
Are you solid enough in your doubts to die without fear?
So you agree that there are parts of the Old testament no longer relevant to us after Jesus? Thank-You!