would like to know
 

I would like to know if there is a software package out there that will enable me to dual boot both linux fedora core and windows xp.

i will be running them on two separate hard drives.

Software Package?
Every linux distro comes with a boot loader (either grub or lilo) that can be configured to boot mulitple os's.
While installation you could have done that. But you can as well do that now. Read your distro's documentation to find out how to configure the boot loader or search this forum (there are many posts about this).