One of the things in Ubuntu that has always driven me crazy is the addition of new items into the grub menu without removing the old entries that likely don’t even work anymore. I’m sure most experienced Ubuntu users already know how to do this, but here’s the method anyway.
To remove these entries, we’ll need to edit the file /boot/grub/menu.lst. You can do this by using Alt+F2 and then typing in the following command:
gksu gedit /boot/grub/menu.lst
Now that we’ve got the file open, scroll down to the bottom of the file where it says “End Default Options”, and you’ll find all the menu entries for the various kernels in here. You can just select and delete the ones you don’t want.
Save the file, and then the next time you boot up you’ll see a much nicer set of options.
Hope this helped in reducing your grub size..................This is applicable only upto distro's like jaunty9.04 which are using grub..