has the power cable come out of the back of the CD drive inside the computer?
This can cause problems.
Or try looking at the data cable that attaches to the back of the CD Drive, if it is loose, this message is often displayed ~ check inside ur machine!
It's too bad you're not adventurous enough to open the case and poke around as what I suspect could be easily fixed by doing so. Basically it sounds like you need to reinstall the driver for that drive, and unplugging the IDE cable and the power cable and turning it on and off and then reattaching the cables will make the operating system recognize the drive as new hard ware and will try to find the appropriate driver.
I use W2k so I'm not exactly sure of how XP is set up but it should be similar. Try going to my computer, right click on your CD-ROM, click on properties, click on hardware, click on the specific drive, click on driver, and click on update driver.
Maybe someone here more experienced with XP can provide more accurate details.
Here it is in step by step for XP
Right click MY Computer
Dvd/Cd Rom driver
Click the + box beside Dvd/Cd rom
right click on your device
right click properties
click the Driver tab
then anwser the questions in the next screen