The Air Force flies the F-16, F-15, and F-22; with the F-35A comming out in a couple years.

The Navy fly F-18s, and will fly the F-35 (C I think)

The Marines fly F-18s and Harriers, with thier own F-35 comming out.

Marine and Navy pilots will often fly off of carriers, whereas Air Force does not. 

The benefits, umm, you get to fly fighters!  You also get paid more than non-flying possitions.  The Navy and Marines get to travel by ship, if you consider that a benefit.  Rumor has it that the USAF treats their pilots better, and you will be able to take your family with you more often.

To become a fighter pilot in the USAF, you need to be an officer.  That means you need a college degree.  Your routes to that would be through ROTC, the USAF Academy, or OTS.  You would then need to be selected into UPT (undergraduate pilot training).  After passing that (and doing very well in it), you could move on to fighter pilot training.  It should take between 5 and 7 years to complete college and training.