Life of Brian was spoiled for me by channel 4 when they showed it as part of their "Banned" season umpteen years ago. i went in expecting to be shocked by the so called offensive humour in it, but I wasn't. I'm not saying it wasn't funny, because it's hilarious but I was lead to believe it was something it wasn't (kind of like most "controversial" things)
Holy Grail does have a lot of off moments but the last scene where the police show up and arrest everyone always gets me.
Just in case you didn't follow that, I prefer "The Holy Grail"