Terminator

It seems Shwarzenegger went to a lot of cyberpunk movies, back then. Which is cool, since you know, it's Shwarzenegger. Besides...

                                          "I'll be back!"

Now, enter Terminator.
I prefered the Terminator 2: Judgement Day, as a kid. Because explosions! Oh, and I had nightmares back then with the part when T-1000 falls into the "lava pit" and starts morphing into every character he had morphed earlier. Scary shit, folks!
 As far as the plot goes, I think the first terminator movie takes the cake. I suggest you to check both of them out.