It’s actually Jason Clarke that plays John Connor. Courtney played Kyle Reese.
As for the post T2 sequels, I think I dislike T3 the most. The truck chase was cool, and the ending was a surprise, but everything else felt like a gutless rehash of T2. The acting was bad all around, and the attempts at humor all fell flat, Salvation and Genysis were bad, but at least there were interesting ideas in them that could have been capitalized on.
I only saw the second half or so of Salvation - it was on HBO one night. I thought it was terrible. Is the first half of that film good enough for me to watch the whole thing now? I know it isn’t fair to judge a film without having seen the first half but that second half I did see just seemed incredibly dull. And Sam Worthington’s acting is just so lifeless and flat.
She’s been in a ton of movies and TV shows that you’ve seen and probably liked. She was amazing in Black Mirror’s “San Junipero” episode, which was one of the show’s best.