If your watching movies, the display should say something like Dolby Digital for example, or DTS if your in that mode for Movies. Sometimes you might see PLIIx during the DVD menu previews prior to the movie. Direct and Pure modes I believe are more for music listening and disregard your bass management modes for movies.
The Center channel is more for dialog in movies and surrounds for surround affects. I'm still a bit confused what you could have been cranking up to blow the Q's.
It doesn't matter if you set the levels for each speaker to 0dB or even -10dB to start, as soon as you run Audyssey they all get reset and changed based on the test results. If your doing it manually, normally people get an SPL meter and match all the speakers to the same pink noise around 75dB or so...
