Please don't think of it as ruining it at all. I am a very uncritical viewer - I usually miss all kinds of things on first viewing. That's one of the reasons that I watch so much on DVD - at least I can watch it several times to get more of the point.

I also like getting different points of view because I think that enriches the whole viewing experience. Seeing your comments certainly got me to watch AvP a second (and third) time and each time I saw something different that changed my perception of the movie. I thank you for that.

I think you're right about the rating too - AvP was strange with its not-quite-but-almost-explicit violence. At least with an R, they can just go for it, no holds barred.