Sounds like beginning symptoms of a dying xbox. When you download the info does it freeze with the image still on your screen? Or does it turn black?
If it freezes but you can still hear the audio with the image, just wait for it to come back. If it freezes with no audio at all, then it could mean your xbox might give out soon. A game could "jump start" the freezing and problems to your 360. This is what happened to my old one with Call of Duty 4. It would only freeze with that game and eventually my xbox gave out.