Good luck on your first butt, they really take some effort to screw them up so you should be good. I normally cook mine at 225, and normally do two at around 8-9 lbs each and have had them take anywhere from 18-21 hours to finish up. I always plan on them taking longer and can rely on the FTC (foil, towel, cooler) method to keep them hot if they get done early.
I normally place a tray with beer in it on the bottom rack to catch the drippings, then the first but on the next rack up and then the next butt either 1 or 2 racks up depending on whether it fits or not.
I like hickory on pork so I think the hickory and apple would be a good combo. After you are done applying smoke then change the water and rotate the racks, top to bottom front to back. This will help even out the cooking a bit. At this point I normally go to bed and then rotate again and refill the water in the morning.
195 is when I pull mine and FTC them for at least an hour before pulling. Don't worry when the temp stalls for a while, this is normal and it will start going up again eventually.
