Won't recognize DVD's

I've had my Dell Dimension 4100 for quite a few years and all of the sudden recently every time I try and play a DVD it acts as if there is no disc in the CD-Rom. Any other software disc or data disc it will recognize just fine. All my drivers are updated and I've even tried troubleshooting it too, nothing works. I just reinstalled WinDVD just in case AND I even uninstalled the drive and let Windows XP reinstall it automatically to see if that would work. Any suggestions?

 

Maybe time for replacement.
You said quite a few years old, nothing lasts forever.
Have you tryed more than one DVD?
Might try drive in another PC.