Problem with stable

[Heretic]

When i click stable from http://www.freebsd.org/es/releases/index.html
release i get,

Document not found -
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/stable.html

Can anyone help me understand the differences between all the versions
of FreeBSD. I was trying to get stable but i cant find it anywhere and
are all very old versions...

For a web production with many users, apache, mysql,php...which version
hould i use?

RELEASE 6.1 or another one? Thanxs for your help