I've used two programs to do it. They did it perfectly, but since it was trial software my .gif animations had text all over them.
Then I found Ulead Gif Animator 5. It's great, except the animation is too slow. I put the delay to 0 (1/100th).
I actually had to convert the .vob file to .mpeg, first. Are there any programs out there, that are free, that make it really easy?