Personally, I think with the universe as big as it is I would be amazed if there wasn't some form of life out there. Even if its lower forms of life (bacteria, fish, animals, etc).
As for UFOs, that's a bit different. Although I do believe in "some" of the videos and sightings a majority of them seem bogus. I think its likely that we come to some conclusive evidence within the next 20-30 years that they exist or not. As for the religious section, I don't think that a discovery of aliens will shake the faith of most anyone who believes in anything. I'm sure we'll have the "odd man out" factor here, but I don't think it will cause mass pandemonium.
Maybe not but it will be shocking.Maybe not chaos,but just shock.