I rented this disc in HDDVD format and played it on my Xbox 360. The movie played flawlessly after it updated, which happens automatically. Before I watched this, I bought Shrek 3 on HDDVD and watched it. Then, after watching Knocked Up, my Shrek 3 wouldn't play on my Xbox 360's HDDVD player. It stopped with an error code. I called Microsoft and they stated the Shrek 3 disc was bad. I knew this wasn't true.
After digging around on the Internet, I discovered that Knocked Up, as well as many movies, puts cookies, that's what it's doing when it states "Web Content Updates" when the movie initially starts, on the HDDVD drive itself. This 11 mb cookie made my Shrek movie stop working. After going to the System blade then Memory then selecting HD Player and erasing the 11 mb cookie, Shrek now starts up beautifully. Whatever update this movie is downloading is causing issues with other discs. By the way, only, so far, Shrek 3 HDDVD seems to be effected by Knocked Up HDDVD's bad cookie.
I tried calling Microsoft to tell them of the problem and the solution I found, but they had no idea what I was talking about. So, I hope this helps those who might encounter the same problem. The movie itself is cute and lighthearted, but the web update needs to be fixed.
I hope this helps.