Well, you dont have to change anything. Its very possible that the Digit DVD might have been faulty.
For the DEC 2007, get it from a friend or something, and ask your newsstand owner if he has any back issues or back cds/dvds. I'm suggesting this because the newsstand I am regular to, has some older copies for people.
If you are a subscriber, simple, return the dvd and wait for a new one. I heard that Digit is quite prompt in these issues.
For Feb 2008, since your PC is like a super computer, read the descriptions in the flash, browse the CD in explorer and install the progs
Come on man, you cant complain for these issues, they are too simple to solve. And forget the DVDs, you can get the latest versions of the progs online.
PS: If normal DVDs also cause any problems, try checking your DVD drive