The retail Season 1 DVDs used for this rip generally include:
These are likely the identifiers for the specific release group or individuals who encoded and uploaded the file to the "Scene" (the underground network for digital media sharing).
The .rar extension indicates the video files are compressed into an archive, a standard practice in Scene releases to ensure data integrity during transfer. Stargate SG-1: The Complete First Season | SGCommand
Profiles on characters like General Hammond and Captain Carter, and a "Behind the Scenes" look with the producers.