first, you should chose ps/2 mouse during the installation if your mouse is USB. By doing this, when your system start, then the mouse works but the wheel donesn't work. then open one terminal to run:kate /etc/X11/XF86Config.
there is one part about mouse like this:
Section "InputDevice"
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "IMPS/2"
Option "Device" "/dev/input/mice"
Option "ZAxisMapping" "4 5"
Option "Emulate3Buttons" "no"
EndSection
make sure that it is"IMPS/2". and if you mouse is USB, then change "?dev/input/mice" into "/dev/mouse". then reboot.
done!
good luck!