A review of the Scottish play

Yesterday I saw Macbeth at the Guthrie. It was pretty spontaneous because I got an email for a $15 ticket. I love their discount program for non-profit employees!
I've never seen Macbeth on stage, but I think it was my first knowledge of Shakespeare. In my third grade Discovery class (name for gifted and talented program at our school), we were given a variety of options for a group project. One of the options was to act out scenes from a play. Of course, me and my friends picked this one. We never chose the science/math ones. I wonder why that program only focuses on our strengths. My math skills were so bad I was in Chapter 1 (remedial math class). I think I was the only kid in both programs. Anways, back to Macbeht, I told my group we didn't need to go to the library to look for a play. I'd bring one from home. So I went home and picked up my grandma's copy of The Great Works of Shakespeare. I have a vague recollection of my dad pointing me to the "Double double toil and trouble" witch's scene. We did that scene and my friend Jorge and I did a Macbeth/Lady Macbeth scene. I really can't remember which one. As I was watching last night, I was somewhat perplexed at what scene we picked. I'm not sure there were any appropriate for third graders.
The production at the Guthrie was really good. I heard it was quite violent, but I didn't feel any of it was gratuitous. It's a violent play. Shakespeare tragedy = lots and lots of death. Did we have to see MacDuff's kids drowned in a bathtub? It doesn't say in the play how they are killed just that it was savagely done. But I actually thought that horrific scene was well done and a good lead to MacDuff bringing back an army to fight Macbeth. The actors playing Macbeth and Lady Macbeth were excellent, although, I never imagined Lady Macbeth to be so sexual.
I actually didn't read Macbeth in my college class because the course only went up to 1600. Such a disappointment to miss out on King Lear, Othello, Henry VIII at the college level. We did read it in high school, and as I was watching last night I returned to my past questions about Macbeth. If he had not heard the witches would he have still become king? Would it have been in a noble way or by killing the king? Even after listening to the witches, if he had not gotten overly ambitious and egged on by Lady Macbeth, would his destiny still have led to king? Or did the witches determine this evil path? Chris and I discussed it this morning and he had a good way to ask it: Are the witches revealing his fate or engineering his fate? (Why is it that Chris can take 10 of my rambling sentences and condense it to 1 very good question? I can only get to my main question if I write down all my thoughts and then edit) What do you think? I'm sure many many people have argued about Macbeth's fate. I could google and find tons of answers, but sometimes I just want to come to my own answer. I like to think he would still have become king, but it would have been in a noble way...shows my outlook on the world and fate I guess.