The mother of all boot loaders is Grub. This based my trials with Lilo, Windows' NTLDR, BSD and Solaris boot loaders.
It boots
100+ systems in my box.
It is the only boot loader that you can use it manually to boot every system in a PC.
In majority of cases you can boot every system with the same 3 lines of commands (extra lines are needed if you have multple installations of Dos, Windows and BSD as these systems were not designed to coexist together).
You can install Grub in a floppy, CD, MBR, any partition with a system or unattached to a system. I can boot every one of my 100+ systems with just a Grub floppy! The published menu is just the collection of commands I would use on each one.
If you are interested in finding a boot loader that is easiest to learn, most powerful to use, most flexible in apllication and actually has the ability to teach you how to boot (by its ability to boot a system manually one step at a time) Grub is the man!
Took me a while to write the above link but please do let me know if you find something better.