I switched to kde briefly while trying to track down the icon issue... It went away UNLESS I ran a gtk app. In that case buttons and other gui objects exhibited the same weird rendering errors.
Option "RenderAccel" "TRUE"
Got rid of the effects, however 2d performance is still WAY inferior to the rage128 xfree card/driver.
As I said in my original post, screen corruption showed up after installing ximian desktop, but 2d suckage started right after I stuck the graphics card in an agp slot ;-), but 3d rocks and I think it's awesome that there's linux support and this forum, thanks nvidia andy et. al.