Replace /dev/BOOT and so on with the actual device names. Boot using the Gentoo CD, chroot
to your install on disk as per the installation instructions and then edit your fstab.
So these lines:
/dev/BOOT /boot ext2 noauto,noatime 1 1
/dev/ROOT / xfs noatime 0 0
/dev/SWAP none swap sw 0 0
...should probably look something like this:
/dev/hda1 /boot ext2 noauto,noatime 1 1
/dev/hda3 / reiserfs noatime 0 0
/dev/hda2 none swap sw 0 0
Of course, make sure you're using the correct device names and filesystem types. If you're unsure and didn't jot it down on a note during installation, type fdisk -l /dev/hda
(if /dev/hda is the disk you're installing on) to see what partitions you have.
Also remove the duplicate entries you have further down in your fstab.