Installing Lion on another MacBook Pro through a bootable DVD but won't show up
Same as you : my brand new MBP cannot read a DVD (it says it is blank), but that same DVD can be read OK from older Macs. I went to an Apple store with that DVD, and they found the same problem, i.e. the DVD can be read OK on some machines, but not OK on others. I left them the DVD, they are going to enquire about it and about why some of their own machines can read and some others cannot.

So maybe your problem is just about that : a DVD which unluckily cannot be read on your machine.

Hope this helps !