Hi Dave,
In the vieo driver settings you should set AA to be controlled by the application (i.e. by SU in this case). However OpenGL settings will only affect the screen appearance of the model what's more, the lower AA settings you choose from the OpenGL settings in SU, the better performance you may achieve with bigger models (although as a woodworker, you may not have extremely big and complex models like a landscape designer with lots of 3D trees for instance).
The 2D raster export is not controlled by the OpenGL settings but by SU itself. When exporting, you should be able to set AA in the options dialogue. If this does not work however, there must be a problem.
a workaround may be what Alan (Fraser) does in practice; export with a higher (say double) resolution and scale your image down in PS (or equivalent) using AA settings there. Actually he prefers this way of exporting / post-processing to straight SU+AA export.
However if you export at 3000 pixels already, exporting at 6000 may be a bit too much. π²