[ubuntu] grub problem after installing ubuntu

Hi,

I got a grub problem while installing ubuntu 12.04.

At first, win xp ran on my pc and it has drivers of C/D/E. Then I free driver C and install ubuntu 12.04 on it by setting up swap area and root /. The installation goes well until almost the last step which prompts error "executing update-grub failed". After restarting the system, it goes to the black screen with:

Error: ELF header smaller than expected
grub rescue>

I followed this instruction https://help.ubuntu.com/community/Boot-Repair

After clicking the "Recommended repair" button, I got the message "Please close all your package managers (Software Center, Update Manager, Synaptic, ...). Then try again. But I'm not running any package managers!

Here is the Boot Reapir link:

http://paste.ubuntu.com/5719103/

Thanks for the help

Li