I would choose two scenes.
For me, the best Zombie scene ever is that part in the original
Night of the Living Dead where we see those things eat the intestines from the people in the car wreck. The movie is from 1968, but this black and white scene is still gruesome, shocking, and gory in 2011 - classy.
This is followed closely by the first appearance of Guthrie in
The Living Dead at Manchester Morgue - very creepy and moody.
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