I don't have a lot of time to reply to this, but there are many recent threads here on the forums about nearly every topic you presented. One of interest to you might be the one in the Mountain Bike Racing subforum about what to expect/what equipment is needed for a first race. There are also many debates regarding the discs vs, V-brake setups here. Might be worth searching some of these discussions in addittion to the suggestions made in response to this post. Good luck in getting the right bike!


-Moab