When a CD is inserted in the optical drive, Windows XP looks for the autorun.inf file, which has instructions to launch a program or do any other task. For CD, the autorun.inf file has the instruction to launch the graphical interface where you see all the contents in a graphical format rather than the regular file explorer. Sometimes due to changes in the OS, the AutoRun feature gets disabled. Here is how to enable it again. You will have to modify the registry for it.
We suggest you make a backup of your registry so that if anything goes wrong, you can go back to your old registry settings.

Go to Start > Run. In the open box, type "regedit" without the quotes. The Registry will open. First save your current registry settings, here is how you do it:Click on file and then click on import and save the file. Now here is how to enable AutoRun:On the top left hand side, you will see my computer, expand it in the following manner : My computer > HKEY_LOCAL_MACHINE > System > CurrentControlSet > Services > CdromClick on Cdrom and on the left hand side there will be a string called AutoRun, double click on it, a box will open, make sure the base is hexadecimal and put the value as " 1 ". In case you want to disable AutoRun, shift the value to " 0 ".