I installed Ubuntu 9.04 with EXT4, it works as it should, except that Ubuntu does not turn off the laptop when it closes.
I do not know exactly what the cause may be due, because I also have problems with the CPU freq.

To get laptop to turn off, I have to press any key when Ubuntu turn off the harddrive.
This problem occurs only when the laptop shuts off while running on battery. Running on the power, it turns off properly.

I've looked in the log, and see "messages" it says in the end before the next boot:

How do I get Ubuntu to shut down properly?

Do you have ACPI enabled? I had a similar problem before, all I had to do was force ACPI to be on.

rabbit2345

I have disabled APM, so just ACPI running.

I have the same problem. How fix it?

Try this:
When you boot Ubuntu and see the grub menu, select the option to boot Ubuntu with the arrow keys (it should already be selected by default) and hit the "e" key to edit the grub entry. Then use the arrow keys to scroll down to the kernel line for booting Ubuntu. Hit the "e" key again to edit the kernel line. Add acpi=force to the end of the line and hit enter. Then press "b" to boot up Ubuntu.
Post back if that fixes the shutdown problem. If it does, then you can add it to the grub menu.lst so that it is used every time Ubuntu boots up. I'll tell you how to do that when you post back.

And welcome to the LQ forums!

I installed ubuntu 9.04 64bit in my Asus notebook, it works fine as buntu 8.10.

Not work...

Are you running 32 bit or 64 bit Ubuntu? THere are some bug reports on Launchpad about shutdown problems in Jaunty. Some possible work arounds are listed in these 2 threads:
http://ubuntuforums.org/showthread.php?t=987699
http://ubuntuforums.org/showthread.php?p=6983391

I am running Ubuntu 32-bit, and the solutions of the links do not work on my laptop.