1) Classic cannot support hardware acceleration because it cannot directly talk to the hardware. It uses OS X to talk to the hardware. Or at least this is how it was in earlier versions.
2) I do believe the PowerBook G3 Wallstreets are equipped with a pre-Rage Pro GPU and OS 10.1 supports down to the ATI Rage Pro but with no OpenGL drivers. And 10.0.0-10.0.4 support only down to the ATI Rage128.