[Alex]

Are you using Windows XP? If so, you can use Windows Movie Maker. It comes bundled with XP for free.

Start the program and choose "Import video" from the menu on the left. Click on the thumbnail for the video you imported. Now you can play it using the controls on the right. Pause playback on the frame you want to capture then click the icon that looks like a camera that says "Take picture" when the mouse is over it. That opens the standard Windows "Save As" dialog box where you can name the vidcap and choose where to save it on your hard drive.

That's how I do it. Maybe some other users will chime in if they use other software.

I hope this helps.