Dogfish Head brewery (out of deleware) is, imho, the best brewery in the Americas, if not the world.
Dogfish Head Craft Brewed Ales | Off-centered stuff for off-centered people
I've never had a beer from them that wasn't mind blowing. Even their IPA is something special - and I typically don't like IPAs.
Try anything and everything you can get from them. It's all delicious, and varies wonderfully in flavor.
That said, I do prefer Belgian ales. Dubbels, Tripels, Quadrupels... all delicious. Westmalle makes a great one. And of course, I can't remember my favorite beer ever, ha! It's that good!