Patrtick, I'll be the fifth person here

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Unfortunately, you require the original TMPGEnc DVD Author file that was used to create the menu, and ultimately to generate the DVD. I use this software all the time. The person here has just been lazy using that background image. They haven't even changed "Untitled Track 1"!!
You can only change things by reauthoring the DVD. You can use TMPGEnc DVD Author to extract the MPEG-1 (720 X 480) file and then do as you wish. I could be wrong but believe you can retain the chapter stops still (but you may have to manually go back and put them in, I'm not sure).
Cliff