Is this antimatter out there expanding into unknown space all around the Universe and is the cosmic background radiation the result of that antimatter reating with the sparse atomic particles it comes into contact with?

The CBR is a continuous microwave emission and well understood with a BB cosmology. Anti-Em produces gamma rays which could be red shifted I guess. Do the numbers, get back to us....

"Can antimatter travel faster than light?"

I dunno, can matter? Probably not. It will follow the same rules as matter cept when they "collide" a dandy little gamma ray photon is produced for each anihilation pair. Anti-matter is actually well understood as we can make it in small but experimentally significant quantities.