Realplayer question

I'm trying to screencap something that I'm watching on RealPlayer - the only way I can think to do it is by pausing the clip, and then using the print screen button to capture it. But then I open that in paint, and I try to isolate what I want and copy it into a new document, and when I copy the image, I get a little black box.

Someone told me I need to turn off the video accelerator to get it to work. Does anyone know how to do that, or have another solution?

Thanks!

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