RE: Vaseline and baby oil
I agree with the above, it is all mostly personal preference. Also, different peds give different advice on how to treat the same issues. The only thing I use vaseline for is to lube the rectal thermometer. I also never use baby oil. Occasionally, when it is really dry, I use baby lotion after the bath on her skin. As for cradle cap, my ped said to just ignore it and it would go away on its own. I use a lotion called Aquaphor, recommended by my ped, for her cheeks (she gets a rash from drool). I get it at Costco/Price Club. It is a little expensive, but works beautifully and is MUCH less greasy than vaseline.
I have never used diaper rash ointment (or anything else) on my baby's bottom. She has only had diaper rash once, when she was ill and had diarrhea for a couple days. It went away on its own after a day. Diaper rash mostly depends on your baby. Some are prone to it and some are not. Of course, good hygiene, frequent changes, and being sure to air dry before putting on the new diaper also help.
I wouldn't even both to try and have "everything" on hand. You'll still need to make a million trips to the store after you have the baby, so have the basics and then just get what you need as you need it.
HTH,
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)