Hanging up on copying files

Hi,

I'm running Vista and have problems when copying text or pictures from
anywhere to anywhere - generally if I copy text from one Word Document to
another, Word freezes up as soon as I copy anything; if I copy a picture from
Firefox and have Photoshop open, it freezes Photoshop.

I'm guessing it's something to do with the clipboard, but I can't find a
workaround. It's a bit frustrating when it happens, and I was wondering
whether anyone knew why it was happening and how to fix it?

Thanks,

Chris