I've recently posted a thread here about my xbox seeing my copied games as a video , the cause of that was a firmware update, I still haven't updated my firmware, but today I tried an orginal Call of Duty modern warfare 2, and with the cd it updated the xbox dashboard, And I was able to play it, but my copied ones still don't work

My question here is, is call of duty modern warfare 2 working just luck or wil any orginal game work? (without the firmware update)