Agree that it is difficult to see the correct Thompson/ Hall marriage.
1851 census has a Mary Thompson in Sunderland - born Gilling 1824, a widow and a housekeeper for a doctor, Charles G Lamotte.
Also note that in 1851 George Hall, a mason, b Gilling c 1819 is in Newcastle - looks like his parents were also Simon and Mary and an older brother.
William