Since the bezel is a METAL band around the periphery of the phone and is integral to the phone antennas, unless you decide to clean it with sandpaper, you're pretty much not going to do anything to it with anything you can commonly get your hands on around the house (unless you live in a chemistry lab.)
Since the cover glass is oleophobic, pretty much any mild inorganic OR organic cleaner will work on it.
The thing to remember is that, since it IS a silicate-based glass, it's really basically a semi-rigid liquid and you should avoid stuff like paper towels or paper products made from wood fiber to aid in wiping it clean. The common microfiber cleaning cloths will work just fine. Even a small amount of isopropyl alcohol won't do anything to it. Stop worrying - it's going to outlast whatever time you will eventually spend using it - IT'S ONLY A TOOL FOR GOD's SAKE TO ACHIEVE AN END PURPOSE. Yes, keep it nice looking (or not) as long as you don't go dunking it in water or dropping it on the floor or sitting on it while it's in your back pocket, it'll work just fine.
One thing to remember in this ever-increasing germophobic society - the human body has many ways of dealing with foreign bodies and, given a normal non-compromised immune system, the more "stuff" you're exposed to on a daily basis, the better off you'll be to survive the world's onslaughts. This means if your iPhone gets a little dirty - don't worry!
AND FOR GOD's SAKE EVERYONE, STOP CONTINUALLY DOUSING YOUR HANDS WITH PURELL AND ISOPROPYL ALCOHOL BASED "HAND SANITIZERS"! You're doing more future harm to your body than the sort-term benefits you might accrue. (From the spouse of a health-care professional.)
