I dual boot operating systems. Is there a free way I can rename one of the boot options at startup? For example, if a boot option is "Windows", could I rename it to "Windows XP" somehow?
There are several programs that could do this for you. If we're talking about Windows 7, I'd suggest trying EasyBCD out; it's free-as-in-beer, pretty intuitive, and lets you manage everything about the Windows 7/Vista bootloader. If you want free-as-in-speech, I'd take a look at installing GRUB for windows; it's the open-source standard bootloader, and is very configurable (though not quite as easy to learn as EasyBCD).
If it is just the XP default bootloader you can edit this information in the boot ini file, either manually or use My Computer Properties > Advanced Tab > Startup and Recovery Settings button > System Startup "edit", be careful what you edit in that file. Back it up before you edit it.