Tradition was to marry in the bride’s church so Saintfield 1st Pres was probably the Russell family’s church. Unfortunately, according to the PRONI website, that church does not have any baptisms earlier than 1854 and marriages earlier than 1845, so you may struggle to find much about that family from church sources.
Saintfield 2nd has records from 1831 and Boardmill Presbyterian from 1846.
Do you have a townland (address) for any of the events, apart from Santfield?
What were the respective occupations of the fathers Robert Gibson and Hugh Russell?
I had a look in Pigots Directory for Saintfield in 1824 to see if either family is listed, but neither is. (Only tradesmen were listed so it doesn’t mean they weren’t there just that they were farmers or weavers and so would not be listed).