Digital BW, The Print

Off topic, but you folks are my fountain of knowledge...

I have a VHS tape that I converted to DVD so I could freeze a frame 
to print a shot...figured it to be grainy but will go very high 
contrast BW and it might look good.

I cannot for the life of me, capture the dvd image (it's a .VOB file) 
to photoshop. I have a couple of screen capture applications but they 
capture the video frame in pure black...figure this is some copyright 
protection scheme, but this was a sequence shot with a video camera, 
not a commercial VHS or DVD. The DVD software I have is Inter Video 
Win DVD 4 which came with the PC.

Do you know if I need some special capture software or different DVD 
player software or what I should try next????

thanks,

Tom O'Connell