Re: DVD's or DVD Burner.?
well only way to know FOR SURE if it's not the discs is to try Verbatim DVD+R DL discs (you can get these for around $1.30 (i.e. 20 discs for $25.99) per disc on newegg)
but depending on your drives firmware in the 360 that could be the reason WHY the discs are not working. because if your using a wave4 (or newer) game on iXtreme v1.6 firmware that is the reason they won't work.
so in other words... if your XBox360 has iXtreme v1.6 firmware on it (i.e. you got a Samsung/BenQ or Liteon) and your using a new game (which most likely either has wave4 or wave5 stuff on it), you will need to use the activate.iso boot disc to get it to work OR update your firmware.