On my laptop, I have Ubuntu running. Now I want to switch back to Windows Vista. Therefore I inserted my install CD and try to boot from the DVD device, but it seems as if the install CD is not recognized, because booting form DVD device is aborted and the normal Ubuntu is started.
Any hints why this? I don't see an error message, I just notice that it is trying to boot from the DVD device but after a minute or so, Ubuntu is started nevertheless.