Fedora always keeps 2 kernels available. It's a fail safe of sorts so that if the new kernel fails to boot you can fall back to the older kernel. Have a look at the file /etc/yum.conf
. There is a line in that file that reads
This line sets the installed kernels to 2. If you are updating again and there is yet another kernel update, the oldest kernel will be removed and the 2 newest will be kept. You can change that number to whatever you wish or you can leave it as is.
To change what is displayed when you see the boot menu open a terminal and type
su -c 'gedit /boot/grub/menu.lst'
This is a text file. Change anything you like, carefully. You can, if you wish, totally remove the older kernel so that only one Fedora option will be displayed. Please do this only after confirming that the new kernel (the entire system for that matter) functions properly. Some of the more common edits to that file may be
timeout=n (countdown timer)
default=n (default OS to boot if timer counts down or if you just press enter)
hiddenmenu (hides the menu and just shows countdown timer)