Multiple Operating System after updated Ubuntu 10.4 installation
 

Whenever I updated ubuntu once installation after I see that there are multiple but same Operating System options Ubuntu is displayed like below during booting up! Why does it show different options? Is there any option to remove or delete these multiple options?

Ubuntu, with Linux 2.6.32-24-generic
Ubuntu, with Linux 2.6.32-24-generic (recovery mode)
Ubuntu, with Linux 2.6.32-22-generic
Ubuntu, with Linux 2.6.32-22-generic (recovery mode)
Ubuntu, with Linux 2.6.32-21-generic
Ubuntu, with Linux 2.6.32-21-generic (recovery mode)
Memory test (memtest86)
Memory test (memtest86, serial console 1152...
Windows 7 (loader) (on /dev/sda1)

dont worry. those are just your kernel versions you can boot from. you have one "OS" but you have other kernels that can run it. kinda like having one car with a switch in the dash to pick a different motor every time you start it.

As mrmnemo said, these are nothing to worry about. If you need to remove them, you can do so by booting into your latest kernel, opening Synaptic Package Manager (under System->Administration), and searching for packages with the version number of the kernel you want to remove ( for example, 2.6.32-21), and marking them for removal. It's generally recommended that you keep at lease one old kernel in case the latest one has any problems.