I run essentially the same setup of VB 4.2.6 with openSUSE 12.2 as the host and
Windows XP as the guest with no problem. The mouse is good in both full-screen
and windowed mode. I did nothing special in the VM configuration.
I do run kernels that I build myself rather than the standard. At present, I’m
using 3.8-rc1 from the mainline git tree.
This was corrected due to another problem ( unable to access to shared folder ).
I had just forgotten to run “Install Guest Addition”
So running this solve both problems.