When I bought my DV camcorder I installed some software that came with it. The software sucks, but before I came to that realization, I had already made it the default for DV autoplay.
The problem is that once you select an app to autoplay, there is NO WAY to change it unlike with other removables (where you can right click on it and change it in it's properties).
Trust me, I did a LOT of research online and could not find any way to do it.
Finally, after a careful search through the registry, I figured out how to disable DV autoplay entirely.
ALL the autoplay handlers are stored in this registry folder: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Curr
I found the app that was being autoplayed when I plugged in my DV camera and deleted it's entry. Now NOTHING autoplays when I plug in my camcorder which is just the way I prefer it.
I'm sure there's a more elegant solution that allows you to reset the autoplay so that you can select another app, but this solves the problem for me.