I second the Lagunitas IPA. It's my favorite of the style.
If you want something that 'everyone will drink' Landshark is fine. So is Coors/miller/bud lite. OR search out a creme ale, Blonde ale (Leffe), or even a wheat. Blue moon is good, even though it's made by coors. I have a keg of it I made and it's fine for hot summer days. I leave the orange out, but other people like it with. To each their own.
Some other choices you might get into:
Brooklyn Lager. Great on a fresh tap. If you're gonna let it sit for more than a couple of weeks, pass on this one.
Any of the belgains if you want to shell out the $$$$$$. Also, you'll need to jack up your serving pressure or the beer will go flat.
Captain Lawrence Xtra Gold is a great beer, and they're local.
If you can find a kolsch or a kolsch-ish they'll go great in a crowd as well.
B