For what it is worth, I second the hypervisor idea. That is what those things are for. If you are going to be a sysadmin for your own business, you cannot shy away from being bold in your learning and investment in learning new things, or _current_ things, I might add. Thank me later. I am not too competent with GRUB2, but I am sure I can dig some info for you. The general idea with GRUB is that it really is something like a bootloader and a primitive OS. In general, all you have to do is edit the "grub.conf" file, wherever it lives (typically on a partition like /dev/sda1 that is typically mounted as /boot on a standalone system). You put an entry for a particular syste that you want to boot and then it just makes it appear on the menu at bootime. But the powerful thing is that you can just walk into a command prompt like a boss and take care of matters from there. This is how I rescue systems, tweak them, etc. The tricky thing is to be able to tell GRUB for each entry in that boot menu where the kernel is. I keep a kernel handy in /dev/sda1 so that I can just boot, and then throw an "init=/bin/bash" as an argument and I get a prompt on the root filesystem that I choose (you give another option for that). Invest some time in learning the booting sequence of Linux. Then learn soem about GRUB. Then experiment (preferably with a VM in VirtualBox or similar), because those boot faster and do not break the system in general. Send us your "grub.conf" that is found in /boot/grub of your main system. I will tweak it for you.