Well, i beat doa4 on story mode twice, but in my xbl achievements, it says i only did it once...wtf

There is an achievment called "beaing Story Mode once"

it doesn't keep track of how many times you beat it, there is no achievment for beating it twice...

if you beat everone's story mode, you'll unlock a few characters (eliot = genfu, hitomi = ein, everyone = helena, someone unlocks leon, i can't remember who, helena = spartan (master chick/mistress chief)), thats the only way you'll get more achievements for beating story mode

ohhhhhh, now i feel dumby