tantrums and the like

Yesterday, Saber had several major meltdowns. I guess the honeymoon is over. All of them were related to him being told no about something. I have been doing some research on line about how to manage the tantrums and I think that the ignoring method is the best. What bothers me is that there are moments that are amazing and he is so much like a regular 4 year old. He is such a sweet, loving and affectionate child. Then there the monster moments, where he kicks, screams and yells and hits like there's no tomorrow. He likes to get his way, no doubt about it. Its a battle of wills, and while I am picking my battles, I am working on protecting him from himself.
I often wonder what causes some of the behaviors-is it the Autism? Or is it the circumstances of him coming to live here? Poor parenting by his birth family? I often wonder if there was some sort of negative reinforcement in his past, because of how he responds to certain things. He can be willfully defiant-like a 2 year old-and he certainly knows when he is doing something wrong. He'll say that was bad or that was naughty. And giggle about it. But, on the other hand, it can also be a learned behavior (from us telling him it was bad). I stuggle with how to discipline him-does he really get it? Does he understand why he is being punished? I struggle with all of this on a day to day basis. I want him to be a typical 4 year old. I know that he won't ever be, but I can hope. There are days when hope is all I have.
I know that his birth family did not know how to manage his behavior, and that has caused some of the issues to be reinforced. I am not accusing them of anything-they just didn't know. Add to that the fact that there are 2 younger kids, Mom stayed at home literally all day and she obviously spent time on line looking for weird cures for him and its a volatile mix. Plus, they are self professed witches, and that makes it even worse. I think its because I am so firm in my faith that it really bothers me.
Add to it, there is a history of chronic ear infections. So far, we've had 2 in 3 weeks, that I know of. When I read his medical history, there was information in there about the possibility of him having tubes put in when he was younger, but birth mom declined. Ugh. The poor kid has problems with chronic pain due to the infections, a fear of his ears being cleaned out or even touched, and a problem taking medicine. Prolonged ear infections will cause permenant damage as well, and he certainly doesn't need any other problems.
I just put a call into his doctor to see what can be done to help him. We need a grape flavored antibiotic, thats for sure. And we need to prevent future problems. We see the neurologist today too, which I am a bit concerned about. I have a list of questions for him too. Saber just went on the potty himself. Yay!!