Your first murder victim?

[Newt]

I think it may have been in a Hitchcock film; so not 'graphic' at all but there was something in the way it was presented that hit me hard with the realization that this person is now dead and that is a really, really bad thing that somebody had to answer for.   I remember being rather stunned and distressed by it.  Life was never quite the same after that.

[El Misfit]

for me, probably ro-man from Robot Monster, it was when he dies in the scene when i saw it

[Torgo]

I think that the first murders that I saw in a film was in the flick Maniac.