Manually removing kernels and kernel modules

Manually removing kernels and kernel modules
(OPTIONAL WAY):

- /boot Contains all the kernel images
- They probably are named with version numbers. You need to be root ("su -") to delete them, and you can use the standard "rm"  
- The module directories are then located at /lib/modules/{kernel_version} , you can delete the ones you don't need there. Be careful not to delete the kernel and
modules you need of course