This can be done through editing the registry. If you are not sure about editing the registry, I strongly advise against it as mistakes can necessitate the reinstallation of Vista. However, if you wish to do this then follow the instructions. Click the start orb and type 'regedit' into the search box. Right click on this program and select 'Run as administrator'. After providing administrative credentials, the registry editor will open. Browse to the following key:
'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\explorer\AutoplayHandlers'. Right click this key and select 'Export' and give the file a suitable name. If you make a mistake, you can restore this key by clicking 'File' and 'Import...' and browse to the location of the file you created when you exported the key. Under this key are some other keys, and the ones you are interested in are 'EventHandlers' and 'Handlers'. The following images show the default settings for these keys.
The next image shows the 'Handlers' subkey after installing 'CyberLink PowerDVD 7'.
Note the addition of the last 3 items. Refer back to the 'EventHandlers' subkey (the 1st image) and click on each of these names in turn. Note that the entry 'PDVDPlayCDAudioOnArrival' as displayed in the 'Handlers' key is represented by the sub-key 'PlayCDAudioOnArrival' in the 'EventHandlers' key. The other entries are similarly represented.
In all cases, right click on the item beginning 'PDVDPlay...' and select 'Delete'. This will remove all 'Autoplay' options for 'CyberLink PowerDVD 7'. Obviously, your entries might be different, but if you use the first 2 images as references you should be able to remove the other entries.