I've hated every Rob Zombie movie so far, he just doesn't get it. He chooses bad actors and gets bad performances out of them. House of 1000 Corpses sucked, Devil's Rejects was better, but was still pretty bad. And he totally whiffed on Halloween.
Michael Myers is my favorite horror villain and as a kid, he scared the shit out of me. His motives were mysterious and his mask made his killing even more unsettling (shows absolutely no emotion). The thing that Zombie didn't realize is what many film makers don't, the unexplained and the unseen is the most frightening tool in a story tellers arsenal. When you try to explain Michael Myers or give him motivations you just turn him into another serial killer with a mask. It's like when you are building up a monster in a movie, you may hear it at the door and it could make the most horrific sounds. No matter what you show when you finally show it, it will be a let down. The imagination of each viewer will create something infinitely more frightening than you could possibly put on screen.
Carpenter made a great decision in not explaining the why behind Myers. People think it's lazy, but no matter how he would have explained it, it wouldn't have had the same effect.