DAY ONE
Here's what I know post Terminator (1). The first movie begins in 2029. The machines are fighting John Connor's Resistance force and losing. As a last ditch effort, the machines decide to send a Terminator (Arnold) back to 1984 before John was conceived and kill his mother, Sarah Connor. To combat their plan, John sends back his own soldier, Kyle Reese, to protect his mother. Reese has been carrying a picture of Sarah around in 2029 that John gave him and he's totally in love with her. While on the run, Reese & Sarah get romantical and conceive John. Reese is killed, but the Terminator is also destroyed. Sarah escapes and at the end she is pregnant, and has started making the tapes that John is listening to in Terminator Salvation. SO--my prediction for T2 tonight is that Sarah is going to DIE. Because, as it said in Terminator Salvation, she's "trapped" in the past. And if she doesn't die, she'd be around in 2017 (when Salvation is) or 2029 (which is where John is). So, I think she's going to die and John is going to keep the tapes with him. Poor Kyle Reese's life is a very short little cycle. He is born after the "nuclear war" that the machines bring about post-1984, fights with John, and then gets sent back to 1984 to die. Also, to answer your question on why the machines are so angry... Kyle explains that they are A.I. that become "self-aware" and turn against the people who created them. Like if Rosie on the Jetsons realized she'd been created to serve a family and decided to destroy them in revolt.

DAY TWO
T2 is set in 1995. After spending years raising John, telling him all about everything, and teaching him to fight, Sarah is in a mental hospital because a) she keeps raving on and on about Terminators and b) she was arrested for blowing up a computer lab. John is with foster parents, when Skynet sends a Terminator (T-1000 version) to 1995 to kill him. Future-John has sent a re-programmed Terminator (ARNOLD! The Hero this time around, I knew it!) to protect his younger self. Arnold explains everything to John and he realizes his mom WASN'T nuts. The T-1000 is crazyyyy. It's made out of a freaky liquid metal and can shape-shift into whomever it wants, and can change itself into knives & such. John & Arnold go to get Sarah out of the hospital but she's already planned an escape. She's terrified of Arnold at first, but once T-1000 shows up and Arnold is helping to save her & John, she realizes what he's there to do. They escape and she decides to go after the creator of Skynet, a guy name Miles Dyson. He's a nice guy, family man, and is on the verge of something BIG after his company, CyberDyne, has somehow gotten ahold of the arm & chip left behind by Arnold#1. After being unable to kill him, Sarah & Arnold fill him in on what he's about to become. He helps them sneak into the labs at his work so they can destroy everything. The police come, shoot him up, and he is left with the detonator to blow the place, and does. Sad. :( The T-1000 still pursues them, but after a long, strung-out battle in a mill, they throw the T-1000 into molten steel. They also throw the arm & chip in so that no one from CyberDyne will find it. Arnold realizes he's gotta go too, and he has Sarah lower him into the steel. Sad face #2.

SO--based on the fact that Linda Hamilton isn't in the 3rd movie, I still think she's gonna go. Like, I'll find that out in the first few seconds of the next movie. Hmm. Also, Edward Furlong is the saving grace of this movie, which at 2 hrs 30 mins is QUITE a doozy.
ALSO--I've decided the one thing that is absolutely ESSENTIAL to getting through these movies with your sanity, is to remember that the only thing that is FACT is the past/present, not the future. Because, I mean, the point is to keep the machines from taking over, and if they do that, then the future changes. And, I mean, TECHNICALLY that means Kyle Reese isn't born and/or if he is, we can't send him to 1984, or anyway there's no need to. Then John vanishes from thin air because he was never conceived. EXCEPT, John already exists. So the only thing that can change is his future. Time travel is confusing, is what I know.
 
DAY THREE
Ehhhh T3 seems sorta useless. John Connor's living off the grid in fear of a takeover he's been told he's averted, but still believes could happen--he has no phone, no credit cards. Not knowing his whereabouts, Skynet sends a T-X to 2004 to kill any/all of John's future lieutenants in the Resistance before Judgment Day (the day the machines take over...). Arnold is sent back to keep them safe. This includes Kate Brewster, who will become John's wife and second in command, and whose father is a head honcho in the air force and has control over Skynet (which has been taken over by the military post-CyberDyne blow-up in T2). Kate & John know each other from childhood, and he just so happens to be stealing painkillers from her animal clinic the night that the T-X comes looking for her... They connect with Arnold, who reveals that he has been sent from the future by KATE, who has reprogrammed him after he killed John in 2032. It's also mentioned a couple of times that John has successfully beaten Skynet by his death (though I feel like not enough is made of that for it to REALLY be true, and perhaps I misheard). John also tells the story of SARAH being given 6 months to live after a leukemia diagnosis in 1994, and her surviving through to 1997 so she could see that Judgment Day (as predicted in T1) doesn't happen. Then she dies. Arnold informs them that Judgment Day was only delayed, and is in fact happening in 3 HOURS. John & Kate convince Arnold that the key to shutting things down in time is her father, so they go to find him. The T-X arrives about the same time, just after Papa Brewster has flipped the switch on the untested Skynet system and things start gettin' funky. He gets shot up Miles-Dyson-style, but not before telling John that the core of the system is at Crystal Peak, and he needs to head there to shut it down. They get there, so do Terminator and T-X (who, by the way, can both shape-shift, as well as create guns out of her arms, and control other machines), and Terminator (I mean Arnold) fends off T-X, just in time so John & Kate can get past the BIG HEAVY CODE-PROTECTED DOOR. Once they get inside, though, they start to cry because they realize that it is NOT the core of the system, it's just a bomb shelter. Arnold's mission was to keep them alive, and Brewster wanted his daughter to live, so he sent them to a location that could survive the nuclear war. Rather than blowing the place up, they hold hands, realizing their fate, as voices of survivors come through the radio, asking for John's guidance. JOHN IS NOW THE LEADER OF THE RESISTANCEEEEE.

I know what you're saying, WHAT IS THE ULTIMATE GOAL OF IT ALL? I THOUGHT WE WERE TRYING TO STOP JUDGMENT DAY? Well, my friend, so did I... but Judgment Day was inevitable, so now I'm pretty sure we're just having a wild ride, all the while simply combating Skynet's repeat attempts to kill off Connor before he beats them. And what of Sarah Connor, lost in the past? I HAVE NO IDEA.