What application are you using to play your DVD's and Blu-Ray discs? I'd recommend trying the trial of PowerDVD 11 Ultra if you haven't already.
DPC Latency could possibly be contributing to your issue. Get DPC Latency Checker from the link in the OP of the "Drivers, Apps, and How-to's" thread and read how to use it on the download page. A good driver to start with is the Atheros Wireless Network Adaptier driver (if you have that card on your system). The Atheros driver version that ships with ASUS laptops has notoriously bad DPC Latency. Upgrade it to version 9.2.1.432 or later.
They may be other drivers that contribute to latency on your system.
What is the "Hardware Ids" of your display from the "Details" tab of the display Properties in Device Manager?
What Antivirus and AntiMalware software have you installed to your system?
I've also seen another thread discussing poor image quality of still images:
http://rog.asus.com/forum/showthread.php?6676-g74sx-Color-depth-reduced-software-problem-or-hardware... This particular issue has proven difficult to resolve.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT