Ah--beer!!
In Epcot, the beer offerings are usually geared to one or two popular offerings from each country. Not really a great selection. As Taryn notes-Molson in Canada. They ought to be able to do better than that.
In Germany, it's Becks. Again, they could certainly improve on that. Mexico features Dos Equis--and so on. My choice of the best beer at Epcot is Rhinges at the Norway Pavillion.
Sadly, WDW beer offerings have deteriorated thru the years. Hardly any specialty brews around anymore (ie The Lodge Brew at Artist Point is gone, Safari Amber at Jikos is gone etc). Most restaurants now carry the "usual suspects"--Sam Adams, Corona, Bass, Bud, Coors, etc
Occasionally you can find something interesting. They have (or had )Hatuey over at Bongo's. House of Blues still has Dixie Blackened Voodo. Citrico's has Fischer's Alscace La belle. Anchor Steam and Sierra Nevada Pale are available at California Grill.
Big River Grille on the Boardwalk has their own micro-brews--Wowzer's Wheat being my favorite. Flying Fish has (or had) Flying Fish Ale.
The lounge with the most beer offerings is Crew's Cup over at the Yacht Club resort. 30-some beers on the list.
Hope this helped--.