Children of the Gods (1) - S1-E1
Trivia: When Daniel tells the others that he believes there is an entire network of Stargates instead of just two, he and Carter figure out that they have to adjust for stellar drift in calculating the new gate positions. She mentions that they should be able to 'MacGyver' something together. This is of course a nod to Richard Dean Anderson, who played MacGyver.
Within the Serpent's Grasp (2) - S1-E22
Trivia: When Teal'c says the long range communication device is somewhat like a television, Jack jokes about if it gets "Showtime." The first 5 season of Stargate SG-1 aired on Showtime.
Answer: While the series was undeniably successful, filming it is a long process, taking many months of often long days. Anderson, after several years of doing this, wished to spend more time with his young daughter, who he felt he was neglecting, and requested that his role in the series be scaled back. Ultimately, he decided to leave the main cast altogether and only make occasional guest appearances.
Tailkinker