When we put a CD-R in it shows a little disc with an hour glass on the desktop. When we click on the drive it says, "please insert disc" as if there is not one in there already. It does not matter if it is a blank disc or one with something on it.  I really need to get these to work so I can back up files and save files on a disc. Could someone please help me? The top drive is DVD RW. It will not recognize or play any type of disc. The bottom drive is DVD ROM. It will play an audio CD. It played an old Family Values Tour CD .It will play a commercially recorded CD. It played or opened up a disc I had for a free 1175 hours AOL disc. It will not recognize a blank/empty CD-R.  
System Manufacturer MEDIONPC
System Model MS-6743
My OS is Microsoft Windows XP Home Edition  
Version:5.1.2600  Service Pack: 2.0  I have never installed or replaced any drivers.  

The bottom drive may have faulty DVD laser, CD laser working OK. Top drive may have failed. Try removing both drives from Device Manager and reboot to allow windows to reinstall drivers. What writing software is installed? WinXP does not directly support DVD writing.
 
      Mike.