I have essential tremor and I've done a lot of research on the net. From what I know you're correct, ET shows itself when people are doing something with their hands like holding a spoon or a cup, but not hands at rest. Parkinson's disease is, as you say, the opposite but based on one small detail like this nobody IMO can make a diagnosis that you have Parkinson's disease. Check out YouTube with words like Parkinson's Disease, Pill Rolling tremor, and Essential Tremor. This might help you. Familial Tremor and Essential Tremor seem to be used interchangeably though in my case I don't know of any family history of ET. One problem is that nobody seems to know exactly what ET is. If you don't have a problem with it and you only wanted some background, I'd say you're lucky. ET frequently (but doesn't always) get worse with time and while there are meds to subdue the effect there's no way of getting rid of it permanently.