Okay, you asked for it
I broke mine down by decade. I'm sure I missed a few...
1950s:
1. War of The Worlds (1953)
2. Forbidden Planet (1956)
3. The Day The Earth Stood Still (1951)
4. Godzilla (1954)
5. Invasion of The Body Snatchers (1956)
6. 20,000 Leagues Under The Sea (1954)
7. The Thing From Another World (1951)
8. Creature From The Black Lagoon (1954)
9. When Worlds Collide (1951)
1960s:
1. 2001 (1968)
2. Planet of The Apes (1968)
3. Fantastic Voyage (1966)
4. The Time Machine (1960)
5. Robinson Crusoe on Mars (1964)
6. Day of The Triffids (1962)
7. Voyage To The Bottom of The Sea (1961)
8. Island of The Lost (1967)
9. Doppelganger/Journey To The Far Side of The Sun (1969)
10. Voyage To The Prehistoric Planet (1965)
11. Marooned (1969)
1970s:
1. Star Wars (1977)
2. Alien (1979)
3. Close Encounters of The Third Kind (1977)
4. Fantastic Planet (1973)
5. Logan's Run (1976)
6. The Andromeda Strain (1971)
7. A Boy and His Dog (1975)
8. Battlestar Galactica (1978)
9. Westworld (1973)
10. Soylent Green (1973)
11. Silent Running (1973)
12. Island of Dr. Moreau (1977)
1980s:
1. The Empire Strikes Back (1980)
2. Blade Runner (1982)
3. Return of The Jedi (1983)
4. Aliens (1986)
5. Star Trek: The Wrath of Khan (1982)
6. The Terminator (1984)
7. Back To The Future (1985)
8. The Thing (1982)
9. TRON (1982)
10. Dune (1984)
11. Star Trek: The Voyage Home (1986)
12. E.T. The Extra-Terrestrial (1982)
13. The Abyss (1989)
14. Alien Nation (1988)
15. Brainstorm (1983)
16. Robocop (1987)
17. Escape From New York (1981)
18. Lifeforce (1985)
19. Outland (1981)
1990s:
1. Terminator 2: Judgment Day (1991)
2. Gattaca (1997)
3. Contact (1997)
4. The Matrix (1999)
5. Jurassic Park (1993)
6. Star Trek: First Contact (1996)
7. Independence Day (1996)
8. Star Trek: Generations (1994)
9. Stargate (1994)
10. 12 Monkeys (1995)
11. Starship Troopers (1997)
12. Deep Impact (1998)
13. Lost In Space (1998)
14. The Lost World: Jurassic Park (1997)
15. The Fifth Element (1997)
16. Armageddon (1998)
17. Godzilla (1998)
18. Waterworld (1995)
19. Johnny Mneumonic (1995)
20. The Lawnmower Man (1992)
2000s:
1. District 9 (2009)
2. Pitch Black (2000)
3. Star Trek (2009)
4. War of The Worlds (2005)
5. Sunshine (2007)
6. Minority Report (2002)
7. I Am Legend (2007)
8. 28 Weeks Later (2007)
9. Serenity (2005)
10. I Robot (2004)
11. Signs (2002)
12. The Day After Tomorrow (2004)
13. Children of Men (2006)
14. A.I. Artificial Intelligence (2001)
15. Mission To Mars (2000)
16. Red Planet (2000)