I upgraded from F14 to F15 using yum, via the instructions on the wiki.
After the upgrade, grub doesn't let me interrupt to select a non-default kernel. I.e., when it says what kernel it's going to boot and is counting down, it won't interrupt the countdown and give me a menu regardless of what key I hit.
Here's my grub.conf:
# grub.conf generated by anaconda
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_jik2-lv_root
# initrd /initrd-[generic-]version.img
# rhgb quiet
title Fedora (220.127.116.11-32.fc15.x86_64)
kernel /vmlinuz-18.104.22.168-32.fc15.x86_64 ro root=/dev/mapper/vg_jik2-lv_root noiswmd LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us
title Fedora (22.214.171.124-92.fc14.x86_64)
kernel /vmlinuz-126.96.36.199-92.fc14.x86_64 ro root=/dev/mapper/vg_jik2-lv_root noiswmd LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us
title Fedora (188.8.131.52-91.fc14.x86_64)
kernel /vmlinuz-184.108.40.206-91.fc14.x86_64 ro root=/dev/mapper/vg_jik2-lv_root noiswmd LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us
BTW, it's a ps/2 keyboard.
I removed hiddenmenu from my grub config, and now I can see the menu, but I still can't move the cursor up or down to select a different kernel.
I tried reinstalling grub with grub-install and it didn't help.
I had the keyboard plugged into the mouse port. Apparently X / the kernel can deal with this but the BIOS and grub can't. My bad.