As per the info on the page, it doesn't come with an Alpha channel, meaniung you would have to create your own e.g. using effects such as Channel Combiner or Shift Channels and consecutive Levels or other adjustments. Still, since they only offer the stuff in compressed formats and the contrast is a bit low, it's gonna look all sorts of awful.
You should be able to key out the black background with the Extract effect:
... though you may need to clean up the matte edge with such effects as the Refine Matte effect.
Then just put a new white solid-color layer behind it.
thank you guys, you've been real helpful. I didnt quite get it like I wanted, but I see what direction i got to take.