check to see if the drive is showing up in the bios. if it not there the drive may have gone south. put a standard audio cd in the drive and watch the green or amber led. the drive should read the cd and spin. if the amber or green led keeps blinking is could be that the drive laser has failed.
Try this http://support.microsoft.com/kb/314060 if that doesn't fix it, then it maybe a bad optical drive, but there are other possibilities. Is the drive recognized in bios? Does it work outside of windows(boot to a bootable cd or dvd)?
99% of the time, nothing is wrong with the drive.
So I can't understand why you keep telling people to replace it. Replacing it won't fix the problem.
Also, do not download "free" software that claims it will "fix" your computer. BIG mistake.
I have not been able to back up my system since longer than I care to remember. To date, I have deleted my registry's upper filters, reinstalled cd/dvd device and updated all out-dated drivers. Yet the cd/dvd device still does not recognize my disk or allow formating, while the device manager reports that the device is working properly. What else do I need to do?