The caution flag (yellow triangle with black exclamation mark) is actually telling you that the drive is not operational. It normally means that drivers aren't loaded, but being that it is a DVD drive, it may mean that the CD drivers from Windows need to be reloaded.
When you see a yellow caution flag next to anything in your device manager, this typically means that there is a problem with that device. When the yellow flag is next to a DVD drive, you may not have all available functionality enabled. There might also be a driver issue with this drive.
There may be yellow caution flag indicating that some operation that you were trying to perform using the DVD was unsuccessful. This may be due to improper copy/ load or write actions. To solve this try to reload the DVD and perform the operation again.
More than likely, you have some sort of problem with either the drive or the cable. I would try replacing the IDE or SATA (which ever the case may be) cable. That will probably be your cheapest thing to try first. With those drives, it either works or it does not.