I have tried ancestry.com out a few times when they offered a free trial. Found virtually nothing. It seems you need a lot of family info to begin with, to search. In my gut I feel most of the info is bound to be hogwash... how could anyone substantiate it? Like virtually all Scots thinking they are descended from Robert the Bruce. I heard that one all my life too, from my Dad's Scottish side.
I've decided that life is too short to spend it looking backwards!