knoppix vesion usually show on the boot screens during startup. There were some problems with mouse configuration (mainly with wheelmouse) in Knoppix 3.4 using the 2.6 kernel, these may have been solved in knoppix 3.6 & later.
open a console, type 'cat /etc/X11/XF86Config-4' & post the result. Should be a readout of your xf86config-4 file.