You should follow jrblevin's instruccion for deleting a kernel, anyway it's a good idea to leave it just in case of anything goes wrong with the actual running kernel.
You can 'comment' the old kernel lines with '#' if you don't want this kernel to appear as a boot option in /boot/grub/menu.lst.
Open a Terminal, log in as root with 'su -" command and type:
#title GNU/Linux Fedora Core 1
# root (hd0,2)
# kernel /boot/vmlinuz-2.4.22-1.2115.nptl ro root=LABEL=/ hdc=ide-scsi hdd=ide-scsi apm=off acpi=on vga=788
# initrd /boot/initrd-2.4.22-1.2115.nptl.img
If I have Windows XP or 98 or whatever, I would like to see the exact Windows version in GRUB's boot menu. I mean, I don't like to see DOS as an option if I don't have it. DOS is not Windows XP, so why do I have to select DOS to start Windows XP?
Well, the solution is editing /boot/grub/menu.lst like this:
1. Open a Terminal, log in as root with 'su -' command and type:
2. Delete 'DOS' and add "Windows XP' like this:
title Microsoft Windows XP Pro
3. Save it and reboot.
Good Luck !