This might be the problem .... from the other forums
UPDATE: Think I found my answer. This article from HighDefDigest states that RE:3 is Sony's first Blu-Ray Profile 1.1 release. Obviously that's the key. Since it incorporates two video streams (the main feature film and the syncronized commentary stream), my guess is that my video card is only decoding the main stream, leaving the CPU to decode the secondary stream. This would make sense, since almost every chapter gives me a few seconds of good playback, then starts to stutter. This would be in line with starting the scene, letting the viewer get into it, then starting the commentary "In this scene we kill more zombies..."
So. The need for the profile 1.1 patch for PowerDVD just became critical with these new releases coming out. Those of you with more powerful processors should be okay, but those of us who live and die by hardware acceleration might be in for a rough ride.