try calculateing the md5sum of the second disks iso file and compare that with the one that the mirror you downloaded it from lists. If they Match then its not the download file and maybe try reburning the cd. if they are different try redownloading the second disks iso.
Ollie:
Alex pointed out a known undocumented feature of FC3, that the ide-cd subsystem is broken when running the mediacheck program with DMA access enabled. The way to get around this is to type in linux ide=nodma when installing. If you do not run mediacheck, the installation completes without error (in most cases). The problem usually is not a bad download of the ISO disk image file.
-- James McKenzie
