dual boot Linux
FWIW, I finally got dual boot going doing the following. Thanks for the replies and help. This is just for closure, in case someone runs into a similar problem. (1) Installed Ubuntu, which redid, when asked, all the partitions and the MBR (SATA WD). (Look ma, no hands.)
(2) Stuck in my old salvaged Win2k hard drive as a second drive. (IDE Maxtor, removed all jumpers). Can now choose which to boot by selecting boot load sequence. Gave up on FC3, at least for now. There's some chatter about a FC3 bug, so maybe this gets fixed someday. I suspect I ran into a FC3 bug, but can't prove that. Never did get dual boot going from a single drive.