My list changes daily, so hard to rank so many great films. I must say I do like a lot of your lists...simply because there is some variety at least. Many top Horror movie lists are essentially the same 20-25 movies over and over again.
1. The Shining (1980)
2. The Thing (1982)
3. Alien (1979)
4. The Fly (1986)
5. The Texas Chain Saw Massacre (1974)
6. Halloween (1978)
7. Lifeforce (1985)
8. The Mask of Satan / Black Sunday (1960)
9. Videodrome (1983)
10. Eyes Without a Face (1960)
Runners up include (among others):
A Nightmare on Elm Street (1984), Rosemarys Baby (1968), Psycho (1960), The Beyond (1981), Zombi II (1979), From Beyond (1986), Fright Night (1985), Night of the Creeps (1986), Re-Animator (1985), The Innocents (1961), Let The Right One In (2008), Martyrs (2008), Inside (2007), The Descent (2005), Slither (2006), Bride of Frankenstein (1935).