JTN, I think having a straightforward birth is more a question of luck than anything else, and there is not that much you can do to make it any different. I know that this opinion flies in the face of all those antenatal classes (especially the ones favouring various natural birth methods) and magazine articles with headings like "How to get the birth you want".
However, most of the things which have a big impact on the birth are external factors which you cannot influence: how big the baby is, how big your pelvis is, size of the baby's head circumference (which most doctors think is more important than weight), your age, your genetic history.
I did everything I possibly could to have an easy natural birth: 2 lots of antenatal classes, healthy eating plan, exercises on birthing ball to encourage optimal foetal positioning, daily perineal massage with almond oil. None of it was any help and I still ended up with an emergency c-section.
I felt very down about this for some time after the birth, but I now accept that because of various physical factors (massive baby, biggest head circumference hospital had seen for some time) I could never have given birth vaginally. I wish there was less pressure on women to "achieve a good birth", because in most cases it is outside your control. When I hear women smugly recounting their quick, easy labours, I am jealous of how lucky they were - but I also notice that the babies are usually tiny 6 pounders!
Sorry JTN, that is probably not what you wanted to hear! But it's something I feel strongly about and I had to give my opinion on this.