If Windows has failed and is unable to boot from hard drive then one way to recover your personal files is to install FreeBSD on a USB pen drive and boot it up. When you have the FreeBSD up and running then you should mount the failed NTFS in read-only mode (one should avoid RW mode in order avoid creating more data corruption on failed partition).
Example mount command:
mount -o ro -t ntfs /dev/ad2s1 /mnt/ntfs
Alternative way to copy all data is to use dd to disk image of the whole drive and then use mdconfig to mount the devices. See the posts below for examples.