Asus N46VZ on Xubuntu 12.04 64 bit

1. Laptop randomly freeze.
It is because a problem in kernel 3.2 with Intel Ivy Bridge Integrated HD 4000 Graphics. It's fix by kernel 3.3, so please upgrade kernel to quantal or raring kernel.
$ sudo apt-get install linux-generic-lts-raring

2. Brightness key not works
Fn+F5 (BrightnessDown) and Fn+F6 (BrightnessUp) not works, it fix by add "acpi_osi=!Windows 2012" in kernel parameter:
$ vim /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="acpi_osi=\"!Windows 2012\""

3. Wireless key not works
Fn+Fn (Wireless Toggle) fix by adding following kernel parameter:
$ vim /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="pciehp.pciehp_force=1 pciehp.pciehp_poll=1 acpi_osi=\"!Windows 2012\""

4. Keyboard backlight key
Please use this tutorial. then add following line at the and of /etc/rc.local:
chmod 777 /sys/class/leds/asus::kbd_backlight/brightness

Add those scripts to Xfce keyboard shortcut in Setting Manager > Keyboard > Application Shortcuts:

5. Touchpad toggle not works
Use the following script then to to keyboard shortcut as step 4
~$ cat touchpad_toggle.sh 
#!/bin/bash
res=$(synclient -l | grep TouchpadOff | cut -d '=' -f2)
if [ $res -eq ' 0' ]; then
    synclient TouchpadOff=1
    kill -9 `pidof syndaemon`
elif [ ${res} -eq ' 1' ]; then
    synclient TouchpadOff=0
    syndaemon -i .4 -k -d
fi

syndaemon is for disable touchpad while typing.

6. Set "3 finger click as middle click" and "disable touchpad while typing" on auto startup apps.

Copy following script:

~$ cat touchpad_settings.sh 

#!/bin/bash

# 3 finger click as middle click

synclient TapButton3=2

synclient ClickFinger3=2

# disable touchpad while typing

kill -9 `pidof syndaemon`

syndaemon -i .4 -k -d

Then add in autostart applications in Xfce. Setting Manager > Session and Startup > Application Autostart

7. Install VGA Hybrid Driver using bumblebee

$ sudo add-apt-repository ppa:ubuntu-x-swat/x-updates
$ sudo add-apt-repository ppa:bumblebee/stable

$ sudo apt-get update

$ sudo apt-get install bumblebee bumblebee-nvidia virtualgl linux-headers-generic-lts-raring

Reboot