Yeah, that's Safari sucking for you. We all have the same problem. Safari's flash engine (whatever it is) really bites and uses huge amounts of CPU time. It's frustrating especially when the PCs of about the same vintage don't suck wind nearly as much when playing flash media.
I'm curious about your usage of QE, though. Have you done performance appraisals with and without QE in VLC? In general, I find my machine to process faster with QE disabled but to _seem_ faster (but really isn't) with QE enabled because things like moving windows, minimizing, or drawing menus seem more fluid when rendered with QE.
Peace,
Drew