1. Auto Start Stop has a button under the starter to disable it on the 28i (it's not available on the 35i). ASS can also be coded by the dealer to default to off and the button will engage it.
2. Oil cooled, with an auxiliary liquid to air cooler:
http://realoem.com/bmw/showparts.do?...92&hg=17&fg=05
I've never looked into who makes the turbo itself, here's the part diagram:
http://realoem.com/bmw/showparts.do?...85&hg=11&fg=50
3. The drivetrain is chain driven, the a/c and power steering (on xDrive cars) are belt driven:
http://realoem.com/bmw/showparts.do?...73&hg=11&fg=25
4. Yes, the mirrors do fold. It may require the Premium or Ultimate package though, best to check with your dealer.
5. No idea.