This method should let you take screenies/vidcaps, including live video streams, using any program and for any file format.
(Windows XP)
-START-
Right Click Desktop -> Properties
Settings -> Advanced -> Troubleshoot
Move hardware acceleration slider to far left & click apply
-END-
This will make sure any program you are capping from or making a clip with bypasses your graphics card acceleration, which is what can cause the dreaded black screenie syndrome.
Remember to turn hardware acceleration back up to full by moving the slider back to the far right when you are finished capping or recording, else some programs might not work properly
🙂
One good program which will take care of all your screen capturing / video recording needs is SnagIt, which can be found here
http://www.techsmith.com/
Good luck and have fun
😀