J.N.
My son is 4 and when he learned to pee in the potty I actually started him standing up. I never started him out sitting. I would most definitely get him standing. It is soooo much easier when you have to use a public restroom that he won't have to sit on a dirty seat! You could have him watch "Daddy" standing to pee, and also put things in the toilet for him to aim at, i.e. pieces of colored tissue paper or Cheerios/Fruit Loops to make a game of it. At his size, he probably will just have to stand in front of the toilet and pee without having to hold it and "aim". Once he gets to learning to poop, he will probably discover by himself that if he starts to pee at the same time he'll need to push his weenie down some so it doesn't go all over. My son kind of picked that one up on his own!
As far as the booster, have you tried it with him yet? I would think he would rather sit in a "real chair" like the big people. I didn't use a high chair after about 2 years old just because my son was getting too big to fit!
With the crib, I think you're on the right track. When he's 3, just get rid of the crib. Tell him you had to give it to a "baby" who didn't have a place to sleep because those are for "babies". You might also want to get some sheets of his favorite character (if you haven't already) that will get him excited about sleeping in his bed at night. I think they even make glow-in-the-dark sheets if that would excite him.
Boys are quite a challenge....good luck!