Great Info here but the whole time I'm thinking this.↑ You have a couple months, start working out NOW. It will make a huge difference in your enjoyment, this is a sport, get ready for it. Might make you feel better in general or keep you alive too. I know, you might be built like an NFL full back but by your original posting, I'm guessing you are not that fit. Your BMI has you just into the "obese" category. I'm hoping you are a bit better than the numbers let on. Loose a few lbs, work on your cardio and leg strength and you'll be miles ahead come December.
To add to the boot rant. Your socks should be THIN. Think lady's nylon stocking thin. This may sound weird but it will help the boots fit better, increase your control, AND keep you warmer by avoiding spots that cut off circulation.
Go ahead and get some used skis instead of renting. Get them tuned up occasionally too and they will work better, especially on ice. You'll avoid the "figuring the skis out" runs in the morning and It will cost less in the long run and you avoid the sh*t show at the rental counter which will increase your time on the slopes and overall experience. Having skis you know and trust will decrease the fear factor too.
About the speed and the fear of it. I know it is really hard, especially for an adult, but you have to get comfortable with acceleration and speed. All the lessons and technique improvement will help you feel more in control but letting go a bit and embracing the speed will help more. Driving a car is a good analogy. If you are driving down a snowy hill and you keep up a consistent momentum easing your way around the corners you will feel OK but try that same hill slamming on the brakes and throwing the car sideways every time you go over 5mph and you'll feel like a cannonball hurling down the hill, right?
One of the most important things in any "movement" activity (driving, biking, skiing, skating, running, etc.) is where you focus your eyes. Start practicing this TODAY. Move you focus way father away than you are used to every time you drive. Look WAY into the corner, not in front of your bumper. Your driving will become smoother and safer but when you do this while skiing, everything will slow down and the speed wont be as scary. You really cannot do anything with whatever is right in front of your skis anyway (especially if you are seeing it too late) so quit worrying about it. You'll have to constantly remind yourself. Even Formula 1 race drivers are constantly telling themselves, "eye up", "eyes up", "eyes up", it works. This and moving forward instead of back when you feel the fear is huge. One of the great things about the sport is that zen thing when you face your fear. Like most things in life, if you are afraid of something and move forward aggressively toward what you are afraid of and face it head on you do much better than retreating and cowering away from it. Remember learning to dive into a pool? Commit to the scary place or do a belly flop. Lessons will help you to a point but you cannot buy courage.
Lastly, take some time if you find a quiet spot on the mountian to stop and look around at the amazingly beautiful place you are in. The better you get the more quiet places you'll find that are really magical.
If you really want to have an exciting time, pack a lunch in your backpack and go into the woods with your lady, build a snow table and have lunch! Just be prepared for the fireworks in the evening!