Go to the Media Lab and get on one of the Macintosh computers with i-Movie and a VHS camcorder attached.
Open i-Movie.
Make sure bottom left slider is to the left (DV) for importing.
Play the VCR.
Click Import when you want to import.  Click it again to stop importing.
Stop the VCR itself.
Click on the clip to see it in the viewer window.
Drag the white triangle below the clip to find the frame you want.
Choose File > Save Frame As and save as a JPEG file. (Be sure to give it an appropriate file name.)
Quit i-Movie (File > Quit).
Open Photoshop, open the image, and adjust size if needed. (This can be done on a PC later.)