IHow can i open up a Dvd project to re-edit?

I have a dvd project from a client, which they want to update with new footage and music. I opened the Video-TS folder which has six files on the dvd. I don't see anything which i can open up or convert over in my editing program to redit it?

the look like this:

VIDEO-TS VIDEO_TS
IFO FILE VOBFile
12KB 8,064KB

VIDEO_TS.BUP vts_01_0
BUP FILE IFO File
12KB 22KB

VTS_01_0.BUP VTS_01_1
BUP File vOBFile
22KB 857,778 KB


Thanks for your help in advance

Bernard

Can you give a little more detail on what you mean by:

[Bernard Ageeb] "which they want to update with new footage and music"

Do they simply want to add some Intro and/or ending footage?

Do they want to retain the current menu structure, or do they even care if you give them a new DVD with similar (but different) menus?

Regards,
George