Run Question

Sounds like a classic case of "wrong shoes" to me.  As for your arm motion, I'm a big believer in the individualized running form, however it is less efficient if your arms are crossing the center line of your sternum.  However, don't do anything that feels too unnatural.  Sounds like your shoes are offering too much stability and you may be suited better for a neutral shoe, but go to a running store to have them look at your gait.  Running too much in the wrong shoes can cause all kinds of injury, so do it sooner than later... i.e. don't wait for your shoes to wear out before you go -- or you're likely to be completely worn out long before your shoes!