I feel like Halloween 2 (the original, not Rob Zombie's bizarre remake) is perhaps the most under-rated of the franchise. The entire original cast and crew got together to make a movie picking up immediately from the moment Dr. Loomis looks out the shattered window to see Myers body missing (er, spoilers for the original Halloween).
The setting is mostly a hospital where Laurie Strode is taken to recover from her encounter with the psycho killer earlier in the night. As Michael stalks the corridors, he takes it upon himself to off what few workers are on duty. One attack on this movie is the gratuitous nudity and the killing of young people fooling around but people seem to forget the first movie had all that, too. I guess, by the time this one rolled around, it seemed cliche but I would argue Carpenter invented the genre and can do whatever he wants with it.
This is the movie where it comes out that Laurie is really related to Myers. I think there is a television cut of the original Halloween that hints at the connection but the original, theatrical cut just had Myers moving on a collision course with this ordinary girl. Speaking of, Jamie Lee Curtis is sidelined for most of this movie, hobbling and hiding throughout the hospital. She does an excellent job radiating weakness and vulnerability. She is still in shock and has no energy left to fight off the boogey man (which was exactly what her line at the end of Halloween 1 implied).
It doesn't have as many awesome moments as the original (which I could list all day) but there is enough here to recommend watching this as a companion to the original. In fact, as a standalone movie, I would say it doesn't really work at all. By the time you are done with both though, you pretty much feel as exhausted and spent as Laurie does at the beginning of this movie.