Good evening Ladies and Gentlemen

Let me start by saying that you are completely at my humor and mercy from the beginning of this speech until the end. I do expect to hear some laughter - preferably for my sense of humor and not for the way that the Groom is dressed today! Personally I would have bought my tux instead of renting.

There isn't much you can say about a guy who comes from the most humble of beginnings. Someone who is at the top of his field at work, who is smart, great looking and always achieves what he sets out to accomplish. A guy who stands out from the rest and who leaves friends and happiness wherever he goes. Okay, that's enough about me, now I better say a few words about Ben!
To see more example speech ideas for opening your speech see:
Light hearted
Introducing the best man speech

Unsettle the groom
Seriously, Ben is a good catch. Lisa is a better catch because she's beautiful, charming, and witty, but Ben is still okay. Ben and I have been friends for XX years so, don't worry, I have lots of juicy stories to embarrass him with, but we shall come to the skeletons in his closet soon enough.
To see more example speech ideas for unsettling the groom see:
Humorous cues