It's a bit funny, the same conversation about how she fires her gun just came up with some of the people I'm doing this winter ecology course with a few days ago. I'm able to ignore the plothole because I don't think the movie tries to be realistic at all .. Maybe it sticks to it's own realism, but if so, it's one where plotholes like that are allowed.
The last film I saw was Aliens. Once again, it kicked ass. Sigourney Weaver is so good in the role of Ripley and the last scene where she fights the queen must be one of the more memorable moments in popular action film history.