I have had the exact same problem with the Nero showtime program. I had to manually go through my computer and reset each video file to open with either quicktime or windows movie viewer.
I haven't found a way to uninstall only that prt of the package.
i have a sony usb dvd writer. the software that came on the disc is titled Sony rev 6.65w. i have used the device on several desktops and laptops. they already had burner software on them nero, sonic and others. today i got the unit out for a fairly new desktop that has nero6 on it. i was reading the box and some of the addons looked attractive. incd4 and nero showtime. i placed the disc in the drive and pc locked up. before total lockup the drive was very noisy. i tried it in the pc's integrated drive and the sony usb. same results. the desktop icons disappear and only the wallpaper is visible. when i eject the disc the icons come back and everything seems normal. any thoughts?