In the future, my son will lead mankind in a war against Skynet - the computer system programmed to destroy the world. It has sent machines back through time...some to kill him... one to protect him. Today we fight to stop Skynet from ever being created, to change our future, to change his fate. The war to save mankind begins now.

while it sounds great, a few changes could've been made to make it more canon with the Terminator mythos. I would have written it as:

In the future, my son will lead mankind in a war against Skynet - the computer system that became self-aware and intent on destroying the world. Machines have been sent back through time...some to kill him... one to protect him. Today we fight to stop Skynet from ever being created, to change our future, to change his fate. The war to save mankind begins now.