|What you're calling a CD may be either a CD or a DVD.|
They are the same physical size, they're both technically Compact Disks, they look the same, but DVDs have a more dense way of storing data on them.
If the disk is a DVD there is probably printing on it that indicates that.
If this is on an older computer, the optical (CD , or DVD) drive must be able to read the type of disk.
E.g. a CD-Rom - only - drive, or a CD-RW (CD "burner") - only - drive (only reads and "burns" CDs), can't read the disk if it's a DVD.
Any DVD drive can read DVDs and CDs .
If the disk is a DVD and if you don't have an optical drive that can read it,
- you need to use the DVD on another computer that can read DVDs.
- or - you need to buy and install one of......
- a DVD-Rom drive that can read both CDs and DVDs (hard to find these days)
- a combo CD "burner" / DVD-rom drive that can read and "burn" CDs and read DVDs (hard to find theses days but you may find one)
- or if your cpu (processer) has a speed of 1ghz or higher, a combo DVD burner drive that can read and "burn" both CDs and DVDs (easy to find - if your computer cpu has a speed of a lot less than 1ghz you can choose to not "burn" DVDs )
Optical drives are not all that expensive, especially if you buy a "bulk" drive (merely a drive in an anti-static bag - often comes with a free version of "burning" software on a disk if it can "burn" disks).
Drives for desktop computers are cheaper then those for laptop computers.
If the optical drive can read the disk.....
- the disk must have an autorun.inf file on it in order for the disk to automatically start loading something. Some disks don't have that.
- the feature of XP that automatically looks for that autorun.inf file and excecutes it if it's there when you insert the disk while Windows is running must be working properly. Sometimes that isn't working properly.
- if the disk does have the autorun.inf file on it (it shows up as autorun when Windows has default View settings), if it doesn't execute when you insert the disk while the computer is running, double click on the drive letter for the drive the disk is in in My Computer.