I use a program called PowerDVD to view the movies on my computer. All you have to do is press space bar to pause, then press 'c' to take a screenshot. A bitmap is saved to some directory, and all I have to do is convert it to jpg.
The only problem that I have is if I try to take a screenshot when a lot of action (motion) is on the screen, the image ends up being very blurry. So I generally have to pause and unpause repeatedly (or use the frame my frame advance button, 't' to find a non-blurry shot).
Forgot to mention... Whether or not you have problems with blurry screenshots may depend on how fast your processor is. I have Duron 600 for what its worth.
Edited by - joeblow69 on Jan 7 2001
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