Recovering ESXi root password is not like most linux system.  You can’t just put ‘single’ into lilo.

You need to boot a Linux CD into recover mode.

mount /dev/sda6 to /mnt/sysconfig

cd /tmp

tar zxf /mnt/sysconfig/local.tgz

vi /tmp/etc/shadow

remove the password fro mthe root entry.

That’s all there is to it, good luck!