Apple released multiple updates for it’s applications, it includes:
Quicktime 7.5 which fixes some security issues.
iMovie 7.1.2 – addresses general compatibility issues, improves overall stability, and addresses a number of other minor issues.
iDVD 7.0.2 – supports general compatibility issues, improves overall stability, and addresses a number of other minor issues.
As usual, those updates are available from the Apple Software Update tool.