I, got the problem with my laptop for reinstalling operating system. The operating system dvd is not working. I have inserted the os dvd and restart the laptop and waited for dell logo when I have seen dell logo immediately I press the F12 button and I have seen boot menu in the boot menu I have seen cd/dvd/cd-rw drive I click and then enter. when I enter I have seen dell logo on screen. This logo goes and comes back again and again. Please give me suggestion as soon as possible.