In Mac OS X 10.4 Tiger, it's now possible to hide iDVD while you're burning a DVD or saving a disc image using the Hide iDVD command under the iDVD menu. However, this can cause the application to unexpectedly quit.
To avoid this issue, do not hide iDVD while burning a DVD or saving a disc image. You can switch to another application in the Dock. This does not hide iDVD, but just sends it to the background.
Note: Encoding and burning DVDs uses a lot of processing power. Do not use other applications that place heavy demands on the system while you are encoding and burning a disc. For more information on burning DVDs, see "Burning your DVD."
If you update to Mac OS X 10.4.1, the option to hide iDVD has been disabled.