<em>'National Lampoon’s Vacation'</em> is a little underwhelming, I thought it was going to be more amusing than it is, though I think there's enough to it that's worth watching. The fun ending with John Candy is what probably nudges this into the rating that I've given. Chevy Chase is at the forefront of the humour, as anticipated. I would've liked him to a bit more of a bumbling mess than he is, a more dumbed…