The alien, yellow sand dunes are actually one of two massive sulfur stockpiles at the Port of Vancouver. 5 million tons of elemental sulfur go through Vancouver each year. The blue crystals are almost the exact color and clarity of hydrated copper sulfate crystals.
Although there are occasional references to his ex-wife and deceased son throughout the series, this is the only time this part of Jack O'Neill's past is explored in depth.
O'Neill's son's name is Charlie. In Stargate (1994), however, the certificate reads Tyler O'Neil. The spelling of Sara O'Neill's name is also different than in the film. These and many other changes were made for the adaptation from the film to the series.
When the Unity crystal lifeform in O'Neill's form comments that Charlie loved to laugh, a poster labeled "Crystals Shapes" is visible on the wall in the background. The Lego set 6190 Shark's Crystal Cave can also be seen in Charlie's room.
When O'Neill opens his locker and looks through the letters and pictures inside the cigar box, the envelope shows his ex-wife's address (and presumably O'Neill's former address), which is 842 Cranbrooke Lane, Winter Park, CO, 80310.