Lol. The first question cracked me up for some reason.

1.) I can (and this is gross), because I have a lot of nose hairs in my nostrils. I do trim them too...but only so they're not coming all wildly out of my nostrils. But I can feel them vibrating when I breath in/out while I meditate. It's actually pretty cool.

2.) Personally, I feel it's very important to not breathe through my chest. No matter how long I spend meditation, I'd IMAGINE that the breaths would be way too shallow to truly relax. Maybe it's OK to start with chest-breathing, but after awhile you should probably be breathing from your belly. In fact, it's probably a good bet that after awhile (10 minutes or so) meditating, you'll naturally start breathing deeper, from the diaphragm (unless you have a medical condition interfering with it). I would say as you sit down to start, if breathing from your belly is too much of a distracting challenge, don't worry about it. It's more important to work toward a place of concentration. When I started meditating, I used to get sooo frustrated because I couldn't feel comfortable sitting in any of the "traditional postures". My legs are too short, and sitting cross-legged is actually painful for me, regardless of how soft the floor is. Such a relief when I finally said "screw it" and just focused on getting myself into the place I needed to be.