This particular fault is quite strange. Although the drive is being detected and reads the contents of a DVD it will not autorun or allow you to right click and select Play in My Computer (Vista Basic x86).
The drive in My Computer is listed as a CD-Drive instead of a DVD-RW. The built in Toshiba DVD player will play the disc if you open it first then click play, but not from My Computer.
The laptop has been running Norton 360 which is what I supect has caused the issue. It also looks as if someone has removed the Upper & Lower filters from the registry to clear the known drive detection problem.
I have tried the following: upper/lower filters check, remove from device manager and re-installing the drivers, removing Norton 360, Intel drivers, turn off UAC and the Microsoft Fix it tool. All to no avail.
Any help would be greatfully appreciated