Removing Old Kernels

[BlueMonkMN]

I'm not sure what to search for to see if this was already answered, but it's a really simple question, I suspect. I've performed a few system updates since installing Ubuntu and I now have 4 different kernels in my boot list. I could edit the boot menu to remove those from the display, but is there a proper way to clean out the old kernels?

[Pumalite]

I would remove 2 through Synaptic (linux-image) and then edit menu.lst, keeping one to work with and the other for emergencies.