Scrambled scenes while editing with Vegas 6

Somewhere, lost in our house, is disk 1 of The Incredibles. The kids have been asking to watch it again, so my wife rented it. Since I had it for a week, I thought I’d make a copy of it to use while we found our purchased disk.

I used DVD Decrypter and then pasted the first three VOBs into Sony Vegas 6. When I previewed it, I found that the opening title sequence was in three languages: English, French, and Spanish. First about 1/2 second in English, then repeated in French, then repeated in Spanish, around and around until the titles end. When the movie starts, the audio and video are out-of-sync by a half second.

The problem is that as I’m editing, the audio is correct, but the video thumbnails in the video track and the preview screen in the bottom right corner are showing a scene from about 30 seconds later in the movie.

What caused this? Did DVD Decrypter leave some copy-protection behind? Would I be better off re-doing the rip with a different ripping software? Is my computer just not powerful enough for Vegas 6 (Gateway laptop, Core2Duo 2.66GHz T7200, 2GB of RAM, 7200RPM HD, 128MB video card with its own memory - not shared with system RAM)?

I’ve already spent way more time than it’s worth doing this. If I had paid myself minimum wage, I could have bought The Incredibles twice. I just want to know where the problem is, so that when I’m working on an important video project, if I run into this problem again, I’ll already have the answer.