Extraction
The Whole image extracted with schtrom (and it checks OK in image tools/stealth check) then it is pretty sure the image is not the problem. (you may also want to try with XBcreator?? in case,)
Burn
Burned with Imgburn on verbatim @ 4x (or 2.4x) with a good burner and the booktype at DVD-Rom, the common cause for burning are covered.
Next thing to verify, is it the backup or your x360?
1) I am assuming the original is playing fine so it is not the flash of your x360 that went wrong.
2) You need to know where is the problem, find a friend that has a working setup. Bring your original and backup to test them on his X360. Bring one of his known working original and corresponding backup and test it on your x360. It will tell you if the problem is the DVD your are producing or your X360 Drive.
We are unfortunately getting close to where the common problem are covered (assuming you do the things as they should

really no offense intented.)
hope it helps,
regards, soso
it cant be a problem with my 360 drive as i bought some copied games with the modified xbox