Ubuntu updates your system with the new Linux kernel version. The new version will create new entries in the Grub menu during bootup, normally it’s the first choice during bootup. For some reason that the new version causes issue, in my case new version don’t install my wifi device and leads me to use wired which is very inconvenient. Since the new version will be selected first during bootup, I decided to remove the newer version and left only the version which I’m comfortable with and i found it irritating to see multiple version in th grub menu.
To remove the versions from Grub Menu, just un-install the related Linux kernel packages using the Synaptic Package Manager. Just open the Synaptic package manager from the System->Administration menu and search for “linux-image-2.6″. this will display all the version installed.
Before proceeding to uninstall please check your current version by executing
garry@garry-compaq:~$ uname -r
Caution! Be careful of not to remove yout current version.