Hope this helps, I have narrowed down my iPad freezing issue to downloading movies at least in my case a rental movie. 60 seconds after turning on my download my iPad freezes. initially did not notice this because I thought it was already downloaded in the background. But when I tried to watch the download I couldn't. So that she had tried pausing the download, and guess what no more freezing. Restart the download and 60 seconds later it freezes again. Not sure why this is happening but that seems to be the solution for my ipad. I will try to update after contacting Apple and figuring out a solution.
out to do this I reset my iPad using the technique of holding the off button and home button for 10 seconds. Then when it rebooted I immediately went into the iTunes store and purchased tab and then pause the download of the movie. In my case it was the movie loan survivor.