My phone has black screen with a red banner saying "download"?

I can't click anything nor turn off my phone. I have a samsung sunburst. What do I do?|||Take out the battery wait then put back in and turn on.|||if you own an iphone, or anything apple related, that means your are trying to download something from online through you safari application if you do not know what it is you are downloading i recommend that you do not download it, it is most likely something that apple would not approve of anyway