If you're not familiar with the Stargate franchise, it started in 1994 with the Stargate movie starring Kurt Russell and James Spader. It then spawned 3 TV series and 2 other direct to DVD movies. The biggest of the series was the first series, Stargate: SG-1, which spanned 10 seasons and over 200 episodes. SG-1 also includes the two direct to DVD movies. We just finished watching the series and the movies and my kids LOVED it! So did I! We just started watching the first season of the second series, Stargate: Atlantis. It's good too. The third series, Stargate: Universe, is on our to-watch list at some point in the future, likely when we finish watching Atlantis.
If you or your kids are science fiction fans and you've never checked out Stargate, boy are you missing out! Get to it, starting with the original Stargate movie. Stargate: SG-1 starts off where the original movie ends.