First off - Tri Girl, I expect lots of pictures!

Another bit of advice - get familiar with the geology (me? no, I'm not biased). Really, it is a nice marker of how far you've descended / ascended, and is tied with the temperature gradient and ecology as well. Plus you will end up with favorite and least-favorite units.
http://www.bobspixels.com/kaibab.org...c_layer.htm#hs

I love the Hermit Shale, because I feel very comfortable on shale scree, and the trails are usually right by the edge of a dropoff so it is very scenic - but other people hate it for that reason! I hate the evil Supai, because it tends to erode easily and cover / wash out the unmaintained and wilderness trails, and it is a long unit to traverse (used to get between gaps in the steep resistant layers, the Kaibab Limestone-Coconino Sandstone, and the Redwall Limestone). The Supai does have some use though, the Redwall Limestone gets it red color from the oxidized iron in the Supai above, forming the gorgeous thick red band in the mid-canyon. (Limestone is gray, and if you see a fresh face of the Redwall it will be gray also).

The Bright Angel is not a very fun trail; the mule trains grind it to a powder, it is as wide as a superhighway relatively speaking, it is not scenic, and has umpteen million switchbacks. The upside is that it is very safe, relatively speaking; lots of water (Indian Gardens, 3 mile, 1.5 mile lookouts), lots of people, and could get bailed out without a helicopter if there are problems. Plus now they have something to dry the mule urine - I remember stinking pools of it, ew! So think up switchback games to play -- we went through the alphabet 3 times before even reaching 3 mile lookout. So even though it is long, it is fairly easy as trails go, and there is not really a need to stay overnight at Indian Gardens (which is not that high up anyway, just on the Tonto Plateau). If I were going rim-to-rim, I would go South Kaibab to North Kaibab, even though the north rim is higher.

You should consider trying to get permits for the Clear Creek area - that is the most interesting place to get to from the corridor trails on the south side. This is a great launching point for dayhikes to a waterfall and to a native site. I've only been on a day-hike partway there, since I haven't been in the corridor in forever... but someday I'll get back there and fill that in. From the North Kaibab, I suggest a day / side trip to Ribbon Falls (easy to find) and upper Ribbon Falls (not so easy to find).

The entire time I've lived and worked in the desert, I've only seen one scorpion -- and that was at 8,000 feet in the White Mountains of California -- fortunately I looked before peeing that night! I like sleeping in the open... one of the few times I bailed and slept on a handy picnic table was during a huge migration of sidewinder snakes in Devil's Punchbowl (Mojave Desert). I am a severe arachnaphobe, but for some reason it doesn't translate into being afraid of sleeping in the open.