I also wonder how Jobs, as buddhist as he was, would rationalize his anger. In the book he repeatedly says "that's how I am", which is pretty much what buddhism tries to undo. He definitely was an irrational man.
Letting go of conceptions was one of Buddha's teachings. "Certain things are predominately innate" is a conception and holding on to that limits progress [1].
[1] Progress in this case means deliverance (enlightenment).
Similarly, I can't know that Buddhism can't levitate you off the ground and make you immortal, but I'm "pretty damn sure" it can't, and I wouldn't get any flack for saying so.
There are many preconceptions I am comfortable letting go of, but not the ones I mentioned--at least not without extraordinary evidence.
That was only a pilot study, but it does appear that meditation is useful for pain. A recent fmri study suggested that one year of meditation caused quite large changes in the experience of pain.
Sexual orientation: Buddhism's stance on sexual morality is pretty simple. No rape and no deception (cheating on a partner, sex with someone underage, and misleading a person to acquire sex all qualify as "deception"). There aren't rules about before vs. after marriage or gender. Buddhism is focused on practicality and harmony, not adherence to assertedly eternal rules.
Immunity to pain: not sure of that one. The brain is a powerful thing, and accomplished yogis (not to claim equivalence between yoga and Buddhism) can get power over their bodies in pretty unusual ways. However, Buddhism's main concern is the reduction of dukkha, which translates as "mental suffering". Focusing on the elimination of physical pain is not a primary goal. This wouldn't even be desirable.
Temper: I think you put your foot in your mouth here. Spend some time around some seriously accomplished meditators. Yes, there are difficult personalities and some strange (even arrogant) people. However, if you look at aggregate differences, the serious practitioners (and it has more to do with depth of practice than identification with "Buddhism" per se) are remarkably (on average; these are aggregate comparisons) calmer, less neurotic, and less self-absorbed than people without practice.
http://www.quietmountain.org/links/teachings/gayrites.htm
Something that complicates this discussion is that there are many varied forms of Buddhism, sometimes saying seemingly contradictory things. While it's important to be able to use the term "Buddhism" for the sake of conversation, we have to be careful of our scope in making claims.
To place this in perhaps more culturally familiar terms for Americans: the Hinayana (even this term is controversial) vs Mahayana branches are as different as Catholics and Protestants, with the Mahayana schools being basically as diverse as Protestantism.
http://dericbownds.net/uploaded_images/medpain.pdf http://www.neuro.cjb.net/content/31/14/5540.short
Spiritual progress is intensely personal and hard to measure, but the existence of anger in a person doesn't make that person "a bad Buddhist". It's not like Western concepts of religion where you're a bad $RELIGIOUS_DEMONYM or a good one. There are skilled people and unskilled people. Steve Jobs was using Buddhist teachings and practices to develop skills that most people don't have and that he probably lacked, to some degree, even unto death. No shock there. Getting to Enlightenment takes a long time.
Once you've gained a sense of what approaches work for you, it's a good idea to get some books and study them. One great thing about zen/meditation books is that you can read them every year and they're still fresh-- there are things in them that you didn't pick up the last time because you weren't ready for them.
While the instructions for meditation are truly simple, taming the mind is not :). There are some pitfalls we all walk into, like attachment to serenity that meditation can bring or getting discouraged by roadblocks. Having a teacher or joining a group helps you not getting stuck.
In cities, there are groups in different traditions (e.g. Vipassana, Zen, Diamond Way). These traditions have similar goals and methods, they can 'feel' very different. So, it's good to sit in with different groups once or twice to see where you feel at home.
With respect to books, I really enjoyed "Zen Mind, Beginner's Mind", but it can be a bit daunting. Philip Kapleau Roshi's "Three Pillars of Zen" is said to be a good introduction.