How can I transfer ownership of a car from a deceased person.Car was inherited by my wife and she wants to gift it to our son.

I had to do it a long time ago, you need a death certificate, and afadavit from her to transfer. You might want to look what's cheaper for taxes gifting it or a bill of sale for cheap.

When you fill out the form put 0 dollers so you don't get taxed on a gift. Nothing extra needed standard transfer form's unless it's a expensive car and has large residual value then explain the situation but should not by anything but standard form's.