Most Open Source code is Free Software, and vice-versa. The definitions are pretty close. The difference is in the philosophy of the movements. He's not against MIT/BSD/Apache/etc licensed code.
I can't find the exact thread right now, but RMS asked someone to use gcc instead of clang when proposed for code completion in emacs... and then refused to allow the necessary changes be made to gcc to allow code completion because evil corporations might use it to extract the AST from gcc and therefore bypass the GPL.
Yes, because he prefers the GPL over non-copyleft. That doesn't mean he opposes non-copyleft Free Software. For example, gNewSense - the distro sponsored by the FSF - doesn't really distinguish between them when deciding what to include.
