First show system events. Second command show events inherent to the process of booting kernel.
tail /var/log/messages tail /var/log/dmesg
To get into single user mode in Linux, stop the boot at grub then edit the kernal you want to boot and add the word ‘single’ at the end. For example ‘kernel /vmlinuz-2.6.21-1.3194.fc7 ro root=LABEL=/ rhgb quiet single'(your line may be different)