I don't believe in UFOs - I do believe in other alien civilizations. In other words, I don't think anyone who has saw one of these UFO's has actually witnessed an alien - however, I fully acknowledge their potential existance.
This belief is based on documentaries I've watched, the thought our best scientists and physicists know what they are talking about and my very limited understanding of the possibility of interstellar travel.
Even this said, I have seen an "aircraft" on my way to work one morning which defies any understanding I know of.
*And if our potential Alien Overlords are monitoring this post I for one welcome you. If you plan on taking over our bodies, please let mine be someone who enjoys Dr. Pepper.
As for preparation we have no chance. If they are the Star Trekkie "we want you to join our Federation" types - great.
If they are the "resistance is futile" type we are screwed. Any civilization advanced enough to travel to this planet will treat us like a rented mule. This won't be Independence Day...it will be Falling Skies where humans will become more of an annoyance than anything. I just hope the ---- probing is kept to a minimum.