Screen capping with PSP8 and WMP

Ok I know this post is in the memories but I just can't seem to get it to work. I'm using PSP8 and WMP (the version that comes with Windows XP) and i can't take Screen captures, everytime i do, the image moves with the picture or turns black. Which is a problem other people seem to have, except they solve it by lowering the video acceleration - i've tried that, set it to low, applied it and then started playing the dvd, then paused the dvd and captured, but once its in PSP it moves. What am I doing wrong?