This is a list of my top ten SF Films.  It was pretty hard to choose them and leave others out, so there are a few honourable mentions at the end.  Yes, I have cheated and attached a couple together.  Rather than try to rank them, they are in date order, which is probably not a bad order to view them in if you are new to the genre.  I have drawn a hard line between SF and Fantasy; the latter might need its own list.

TOP TEN

Metropolis (1927)

The Time Machine (1960)

Dark Star (1974)

Wizards (1977)

Star Wars (1977); The Empire Strikes Back (1980)

Alien (1979); Aliens (1986)

Blade Runner (1982)

Brother From Another Planet (1984)

Galaxy Quest (1999)

Serenity (2005)

Honourable Mentions

Rollerball (1975)

Mad Max (1979)

Terminator (1984)

Predator (1987)

12 Monkeys (1995)

The Matrix (1999)

The Marvel Movies (2008-2019~)

Moon (2009)