There are many I agree with on this list... There are a few I just rented from Blockbuster that I need to return which include:
House of the Devil & Zombie Diaries
I love Zombie movies and some of my favorites are:
Night of the Living Dead
Zombi 2 (Known as Zombie here)
Dawn of the Dead
City of the Living Dead
28 Days Later
Children shouldn't play with dead things
Return of the Living Dead
The Beyond
The Plague of the Zombies
Re-Animator
Dead Snow
Planet Terror (was ok)
White Zombie (B&W)
Zombieland (Great movie)
Revenge of the Dead
Day of the Dead
Deadgirl
Shaun of the Dead (Funny and violent)
Braindead (aka Dead Alive)
Return of the Living Dead 1 & 2
As for slashers I enjoyed
Halloween, Halloween 2,4,5,6 (Producer's Cut)
Friday the 13th, 2,3,4,6,7
Hellraiser 1,2,3,4,5,6,7
Sleepaway Camp
Slumberhouse masscare
My bloody valentine (original)
Black Christmas (original)
Misc. Horror flicks
The Exorcist ***** (SOOOOOOO SCARY!!!!)
Jaws **** (SOOOO SCARY) lol I hate sharks and demons
Phantasm
Serpent & the Rainbow
People under the stairs
last house on the left
evil dead 1,2,3
Susperia
Tales from the Darkside
Inferno
Carnival of Souls
All Universal Monsters (Frankenstein, Dracula, Wolfman etc..)
The Crazies (original & remake)
Deep Red
Tenebre
Texas Chainsaw Massacre (Original & Remake)
Dog Soldiers
An American Werewolf in London
An American Werewolf in Paris
Gingersnap
The Ring
Candyman
The Grudge
Final Destination
Saw
Psycho
House of 1,000 Corpses (I enjoyed this because it was just disturbing)
That is all for now until I can remember more. I'll let you know what I think of the rentals and if they are worth buying or not