Some obvious advice from the Official Xbox Magazine
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Once you have inserted a game disc into your Xbox 360 it is imperative that you do not then switch the consoles position from horizontal to vertical – or visa versa. In doing so you run the risk of the disc within being permanently scratched and good for nothing more than placing a hot cup of coco on.
With the Xbox 360 powered and a DVD inserted, the disc rumbles along at such a rate that if the unit is moved substantially it can clatter into the hard surface of the drive itself, leaving the disc with fatal engravings.
Microsoft have themselves warned you of the dangers of playing twister with your Xbox 360 in the units accompanying manual. Remember that? It’s the book you immediately discarded with all the green bags the Xbox 360 came packaged in. The appropriate section reads:
IMPORTANT:
To avoid jamming the DVD drive and damaging discs or the Xbox 360 console:
Remove discs before moving the console or tilting it between the horizontal and vertical positions.
Never use cracked discs. They can shatter inside the console and jam or break internal parts.
When the console is vertical, do not use discs that are smaller than standard DVDs and CDs.
So, unless you have a penchant for £40 silver Frisbees we suggest you take heed of these wise words, pick an appropriate orientation for your Xbox 360 and only change this whist the power is off. Oh, and don’t water the machine either. That is also very bad…"