[Calavera]

Now, I'm fully aware that I should be the last person to give advice on the subject of humor, but I do have an opinion as a people-watcher. Pop culture references are your best friend, especially throw-back pop culture references. But, please, no "I just saved a ton of money on my car insurance by switching to Geico!" jokes. They have been officially killed dead and every time someone does it, I die a little inside. Note: "Leave Britney alone!" is also in the grave.
Chances have it that the adults you will have in the audience are your average run-of-the-mill people and that may keep them satisfied. However, if you sense that there might be an intellectual or a computer nerd in your audience, throw them a bone. Teens might enjoy a Napoleon Dynamite joke. Basically, stereotype people but don't go into offensive territory.