These are the official FreeBSD 4.11-RELEASE ISO images as downloaded from:
ftp://ftp2.freebsd.org/pub/FreeBSD/ISO-IMAGES-i386/4.11/

The MD5 hashes for these images are as follows:
MD5 (4.11-RELEASE-i386-disc1-gnome.iso) = 80c6b06b83432efc6cbe1cff3ebd893f
MD5 (4.11-RELEASE-i386-disc1-kde.iso) = 84921fe6b6b4bfd3f7011788985d34e2
MD5 (4.11-RELEASE-i386-disc2.iso) = 73553999f9f8e2e49222ba14e8ecbde5
MD5 (4.11-RELEASE-i386-miniinst.iso) = 28b006bcdf5df8b8b7e8f1831085cdae

Note: Most FreeBSD installs will only require either version of disc 1
unless a large amount of precompiled ports are selected during installation.