How do I RIP a still image from a DVD movie?

Can someone help me, I want to rip a still image from a DVD movie, but in HIGH QUALITY! I know how to make a screen shot, but there not very high quality. I would like to keep the DVD quility. think it has to be possible, since lot of DVD/Video editing utils make thumbnails to, so you should be able to do the same at high quality, right?

Can someone give me some tips or names of programs to use?
all help is welcome! thanks

Certainly PowerDVD will let you do this. I’ve done it a few times & the quality is excellent.