Yes, getting a PPL would help.  (That's not your biggest concern now.) 

It would not be too hard (it is one of the more common ways to become an airline pilot)....if the airlines are hiring when you get out.

Here are the USAF medical requirements.  Other services are different.  The civilian field is pretty open. http://www.wantscheck.com/PilotSlotResources/MedicalTips/tabid/68/Default.aspx

I wouldn't reccomend that.  I don't know the chances, but the AF has been cutting personnel lately.  The higher ups realized that cutting people would not pay for new aircraft and are rethinking that, but I doubt the AF will be hurting for pilots any time soon. ***that is mostly my speculation though.

Yes, the majority of pilots in the USAF are NOT fighter pilots.  We have transport, AWACS, recon, tankers, VIP transport, helicopters, and some others.

I really don't know a whole lot about that route, but I think there is info at www.wantscheck.org or in their forums.

While the USAF does have helicopters, we don't have nearly as many as the Army.  Your best bet would be in the Army.  USAF helicopter pilots go to UPT and learn on the Texan II first, then track select to go into helicopters (with further training in UH-1s).  I don't know how many helo slots there usually are, but I'm going to ...

As a guess, I would say your chances of flying are very slim. However, I am not an expert.  Go to www.serviceacademyforums.com and ask this question in the DoDMERB section for a more enlightened answer.

Neither is required to get into USAFA.  I believe Private is on the activities list for the application.  That means it will be one more positive thing on your resume.  Most people here do not have their PPL, so it is not extremely important.  It is a good thing though. Grades are much more important to the admissions ...

Pilots usually try to avoid dying for their country.  They  try to make the other guy die for his.  ;)  Seriously, that is a good thing to acknowledge. Where are you in the process?  Middle School, High school, college? What are you involved in (clubs, sports, community service, job)? How are your grades?