Additionally, you may see one's with a .pae extension, these allow - on a 32bit install - all your memory to be seen/used. (non .pae can only "see" approx 3.3GB out of 4GB memory)
Also you will see some with the .bfs extension which may help optimize your system. (web search for what .bfs means)
One thing I would suggest is only installing one kernel at a time; you can always try another later on.
When you reboot, that kernel will be the topmost entry in your boot menu. Also, that first boot may take a few minutes to get to the desktop as it's "building" itself into your system so patience is required