Image Quality From DVD Caps?

Just wondered if anyone knew how to get the best quality image stills from DVDs?

Which software package for grabbing stills offers the highest quality and, is the quality of the DVD itself any correlation to the quality of the caps you can grab?

Ive never grabbed stills from DVDs before so dont really know much about the process, any help you folks can offer would be appreciated :)

Regards,

Lee

you can use powerdvd from cyberlink.
you can also rip it to your hard drive and i think
that is the best way to get stills from dvds.

I think the quality sucks no matter what program..I use imovie and FC. Then you can clean it up in PS.