After upgrading to 11.10 I can't change the launcher icon size to smaller.

I've tried to change it using ccsm, like described in How can I configure Unity, but the changes take no effects (restarted, tried sudo - still big icons). In the previous version of Ubuntu this solution worked.

How can I change the icon size?

(BTW, how can I know which Unity (2D vd 3D) I'm running and switch between?).

Edit:

Looks like I'm using Unity 2D and have some problems with graphics:

me@my-laptop ~ $ /usr/lib/nux/unity_support_test -p
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
Xlib:  extension "GLX" missing on display ":0.0".
Error: unable to create the OpenGL context

Edit 2

me@my-laptop ~ $ lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 18)
01:00.0 VGA compatible controller: nVidia Corporation GT218 [GeForce 310M] (rev a2)