You are unlikly to ever burn out a console dvd or HD-DVD or Blu-ray drive playing movies.
Games however require fast load times and run the DVD at high speed to do it typically over 10X normal pace and thus cause more vibration , more wear and work the components harder, as they constantly hunt tracks speed up and slow down during game play.
Movies only need to read at a lesurely 1* or 1.5* the drive only needs to spin slowly for movies and does not need to hunt tracks so you are very unlikley ever to have problems playing movies.
One advantage of the Blu-ray for games is it can transfer more data at lower RPM than DVD can so generally the drive does not need to spin as fast (well current PS3 drive is only Blu-ray X2 speed anyway !).
I found this info here
http://www.answers.com/topic/optical-disc-drive?cat=technology
"For DVD base speed, or "1x speed", is 1.385 MB/s, equal to 1.32 MiB/s, approximately 9 times faster than CD's base speed of 200-500rpm. For HD DVD drive base speed is 4,57 MB/s, equal to 4,36 MiB/s. For Blu-ray drive base speed is 6,74 MB/s, equal to 6,43 MiB/s."
I think Blu-ray and Hd-DVD base speed is probably around ~2.5 X DVD base speed
A 12*DVD is spinning at similar rate to a 4.5* Blu-ray drive.
This explains why the 360's drive at 12*DVD speed is actually not much faster than the PS3's far slower spinning 2* blu-ray drive (which is spinning at similar RPM's to a 6*DVD).
PS3 number 1 fan
