is there a blank dvd in the drive? if so, that can cause idvd to launch. either way, it takes a trip to the system preferences. on the cd/dvd pref pane choose what you want the mac to do when you insert blank cds/dvds, and video/photo/music cds/dvds. i personally hate have apps launch when i stick a disk in, so i have them all set to either ignor or do nothing. the only other thing that you could do is goto the users/accounts pref pane. but to be able to make any changes here, you have to be an admin. click on the user account you want to edit in th elist on the left. now on the right there are some tabs, one will say login (or startup) items, or similar. here it will list all the apps that start up when you login. if idvd is listed there, just click it once and then click the minus (-) button at the bottom of the list. remember, there are some things that do have to start up with the mac to work, and they may be listed there, so don't just delete anything out of this list unless you know you don't need it. some examples would be if you have any nonapple usb controlers, like i have a microsoft mouse and keyboard, and their software is listed there.