First off, I'm sorry that you went through that with your first baby, and that you're in a less than ideal situation now.
Secondly, there's nothing wrong with needing a c-section to preserve your own health / bodily integrity. Even with the advantages of vaginal birth, a c-section is still a relatively safe way to give birth, and it can be a positive experience. I don't know much about your condition, but if the choices really are between a controlled surgery and a high chance of uncontrolled (and possibly permanent) damage that will cause you to require repairs and suffer through other problems after the birth, it sounds like a c-section is a good choice for both you and your baby.
The first thing I would do is look into a c-section birth plan. There are some good templates out there that will help you think about things that will be important to you during the birth. A lot of the things you would be concerned about during a vaginal birth still apply. For example, what kind of anesthesia will you have? Not just during the c-section, but in recovery. Do you want to avoid anything that will make you sleepy or out of it, or impair your memory? If you're planning to breastfeed, you'll want to make sure that the anesthetics don't interfere with that.
Who will you want with you during the surgery? Can your partner be with you the whole time? How about a doula? (If you would have wanted a doula for a vaginal birth, it's still a good idea for a c-section!) Do you want your doctor to remove the screen so you can watch your baby be born? Do you want your baby placed on your chest immediately; do you want to try to nurse while the doctor closes you up? Does your hospital allow the baby to stay with you in recovery? After my last c-section, my son was placed in my arms right away and never left my side. Some hospitals take c-section babies to the nursery by default -- if your hospital does this, can you get around it? If the baby can't stay with you, can he stay with daddy (or a family member) instead?
As for the double layer suturing, I think that's just good practice. Mainly it's a concern in case you want to VBAC in the future, but there's no reason not to ask for it. Also consider whether you want stitches or staples on the outside. I think stitches are supposed to be better.
Also, March of Dimes recommends waiting for labor to start naturally before having a planned c-section. That way baby gets to choose when he or she is ready to come into the world, and you have less concern about iatrogenic prematurity. Less convenient for the doctors, but better for baby.