Problems with Xpert 2000 and the Athlon

My setup:

Athlon 600
192 megs of PC 133 RAM
FIC SD11
Xpert 2000 w/ 32 mb, 2x AGP
SoundBlaster Live Value
Windows 98 SE

My question:
My computer has a real poor quality of playback of DVD and streaming video. I have the latest versionof DirectX and I am using both QuickTime and RealMedia in my playbacks. A perfect example would be the choppy playback of the X-men movie trailer. There are no overt conflicts between anything and I have bandwidth out of the yin-yang. I am beginning to suspect that there may be an issue with how the VIA chipset deals with my video card. Suggestions?