"By default I chose to install the mbr on /dev/hda
It loaded fine, but upon restarting it just goes to win."
Use a rescue CD to boot into your new Fedora Core 4 system. Then edit your bootloader configuration file to straighten out the problem. If you are using lilo then the configuration file is /etc/lilo.conf. If you are using grub then the configuration file is /boot/grub/grub.conf.
After you have the bootloader configuration file straightened out then reinstall the bootloader to the mbr. With lilo the command is:
With grub the command is:
Here is a grub manual:
Here is a lilo manual: