For example, PowerDVD and Nero ShowTime.

If your using Windows Media Player, it probably won't allow you to do it. But, I don't know this for a fact.
I use PowerDVD and love it.

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In PowerDVD, you simply click on the camera icon that is visible on the "control panel" (looks like a picture of a hardware DVD player and controls) you can have visible right on your computer screen. I can't imagine it being any easier or convenient.

Although I understood what Random is saying, you might get a little confused...
PowerDVD is capturing the image directly from the source, NOT making a screencap.
Therefore, it is the highest-quality you can get, as it is a direct copy of the original.
Captures of video are going to be limited by the quality (i.e. resolution) of video images. Typically, 720 x 480 pixels is the full-screen resolution on a normal DVD.
They will not be as high a quality as good high-resolution stills, for example.

This is much better than trying to take a screencap (i.e. a capture of what you see on the computer screen, as opposed to a source file). Because, as Random correctly points out, they are not going to be as good a quality.

PowerDVD will allow you to capture the original source size, or capture an image the same size as your displayed playback image (which you can determine by simply dragging the size of the playback window to the size you want), or allow you to specify a custom size to capture.

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"ÉVERYTHING men's hands do I'm nót interested in to see! Keep them out of view!"

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