seeing taskbar during medialab experiment

Hi, as I run my medialab experiment and it switches into direct RT or a word document (from for example powerpoint slide shows), I see the taskbar at the bottom of the screen. Obviously I do not want participants to see this, or even worse, use it, how do I get rid of it?
I was also wondering whether there is a way to shorten the time it takes to upload these files, now it seems as if the computer is about to crash as the screen turns black or purple and stays that way for a while.
Thanks for your response,
katherine

If you mean the Windows taskbar, try right clicking on it and select "Properties". Then make sure "Always on Top" is de-selected as is Auto-Hide. That ought to fix it but let me know if it doesn't.

As for the second question--which files are you referring to?

-Blair