Editing the Grub menu does remove the options but leaves the old kernels cluttering up your harddrive.
If you want to clean out the old versions - open the "Synaptic Package Manager" and remove the old versions of the kernel (Quick Search "linux headers" and select the appropriate version numbers). Keep the last 2 or 3 just in case. Ubuntu Grub menu will automatically reconfigure. Once you've finished do a "sudo apt-get autoremove" to get rid of any un-needed packages.