Well, it looks like there’s either something wacky with my hardware. After 11 tries, I could not get the Fedora Core 3 installation done on my Dell Dimension. I had to revert to some old Redhat 8 CDs I had, install a basic installation on a tiny partition and manully add a reference to boot into FC3.
I wish there were some logs or something that would tell what the error was but this was definitely a strange one.