I stumbled across this thread when trying to solve my Play/Pause and "Media" key issues as well. I wanted Winamp to happen when I used those keys.
I had problems getting Microsoft Multimedia keyboards (natural and un-natural) to spawn Winamp when using the Media or Play/Pause keys. I played around with some settings and discovered this (in Windows 2000 SP4, IntelliType 5.x):
* Leave the keyboard setings for those keys as default.
* In all other media players (WMP, Real, etc.), set them to NOT play audio CDs.
* Set Winamp to play audio CDs, expressly with the checkbox for "Launch Winamp for audio CDs" in Preferences | General | File Types.
That's it! Now ALL the media keys work exactly as I'd like them to. I also verified that the "Set Program Access and Defaults" Windows tool was set to use the default media player.
So it seems that somewhere in the registry maybe is a setting about default media player and that is keyed to CD playing. I almost never play CDs as I've ripped them all to MP3, but when I press Play
or "Media" on the keyboard Winamp loads
my last MP3 playlist and is keyed to beginning of the last song I was playing!
Perhaps a registry genius could tell us how to do this and leave CD playing to another app as some may like...