I have just begun my search on the Duncan side. All of my informaiton is coming from information posted on Ancestory.com 9Ancestory World Tree Viewer. Here is what I have on the ones you asked about.
Ann Hall's parents (Richard Hall b: abt. 1704 and Ann Allen b: abt. 1708). The only Mary Fleming "Molly" I have so far is George (1729 or 1730 -1783) and Ann Hall's daughter.
They also had a son names John (abt. 1758-abt. 1778) Keep in touch. Thanks for your help. My e-mail is firstname.lastname@example.org