Everything was going fine and then... I upgraded to TIGER. Now my IDVD3.0 doesn't work. I will burn my disc and the program will go through the motions, encode, etc. But, when it comes time to burn the program stops.

I had the same problem with iDVD 4. Very unreliable burns. I upgraded to 5 and that solved the problem. There are many new features in iDVD that you will appreciate. It is well worth the upgrade. Especially since you will be going from version 3 to 6. The other apps in iLife like iMovie are also improved in ways you will appreciate.

I don't use iDVD, but it sounds like Ernest is giving you good advice. If you're determined to get version 3 to work under Tiger however, then the place to go would be Apple's tech support forum here: http://discussions.apple.com/forum.jspa?forumID=893

When I burn with iDVD it is very unreliable so I just save it as a disk image and burn it with Toast. This happened with ver 4 and 5 in Panther and Tiger.

Nathan, What is the workflow for doing that?