nano /boot/grub/grub.conf رو بزنید و مقدار default=1 رو به default=0 تغییر بدید و بعدش ریبوت کنید
کد:
# 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/VolGroup00/LogVol00
# initrd /initrd-version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.18-371.8.1.el5xen)
root (hd0,0)
kernel /xen.gz-2.6.18-371.8.1.el5
module /vmlinuz-2.6.18-371.8.1.el5xen ro root=/dev/VolGroup00/LogVol00
module /initrd-2.6.18-371.8.1.el5xen.img
title CentOS (2.6.18-308.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-308.el5 ro root=/dev/VolGroup00/LogVol00
initrd /initrd-2.6.18-308.el5.img