This article is from the CD-Recordable FAQ, by Andy McFadden (firstname.lastname@example.org) with numerous contributions by others.
There are two basic approaches: (1) run the uninstall program, or (2) make
changes to several entries in the Windows registry.
You CANNOT disable it by killing a task.
You CANNOT disable it by un-checking it in msconfig.
You CANNOT disable it by removing it from the system StartUp list.
All these really do is stop the DirectCD control interface from running.
The icon is gone from the system tray, but DirectCD itself is still active,
which you can verify by inserting an unfinalized packet-written disc. If
DirectCD were actually disabled, the disc would be unreadable.
Writing data to such a disc without the user interface component active
can lead to data corruption, because some of the safeguards are no longer
in place. It's like you've taken the steering wheel off the car while
it's still rolling.
If you do choose to use one of the "easy" methods, you will probably be okay
so long as you don't try to write to a disc with packet writing.
DirectCD puts some drivers in C:\Windows\System\Iosubsys\. The set appears
to be CDUDFRW.VXD, CDUDF.VXD, CDRPWD.VXD, and CDR4VSD.VXD. If you are
having trouble un-installing DirectCD, check for the presence of these
files, and rename the extension to ".VX_" if found.
NOTE: the DirectCD icon in the system tray is different from and independent
of the "Create CD" icon that Easy CD Creator 4 adds to the system tray. You
can get rid of that by right-clicking on it and telling it not to load.