Are you frustrated because there is no completely blank theme in iDVD? Full Frame (from iDVD5) doesn't cut it, since you can't remove the annoying background shape in the title text. Or can you?
Yes, you can! Just remove (or rename) the file named...
D3E3A877-38F7-11D9-90CD-000A958D65FE.tif
You'll find this file buried in /Library -> Application Support -> iDVD -> Themes -> iDVD 5 -> 0016_Full_Frame.theme -> [Control-click and choose Show Package Contents] -> Contents -> Resources -> FullFrameTitle.pox -> Contents -> Material. Easy!
Now iDVD won't show the shape any more, nor will it complain about the missing file. The end result is a completely empty theme to customize as you see fit.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20060221045930743