Take it from a Belgian: Jupiler is nice for serious drinking, but you should try some beers with more taste ;-) A good start is LEFFE, which comes in different types. A little more of an acquired taste but liked by many foreigners, is CHIMAY (take the blue version). If you're looking for something stronger, consider DUVEL (Devil in old Dutch), but beware of its horns ;-)

If you go to Delirium Cafe in Brussels http://www.deliriumcafe.be/home/?lang=en you can choose out of more than 2000 beers!

Jupiler beer seems to be the most popular Belgian beer on sale when i was last there. The other is Amstel but i prefer Jupiler.

There are way too many. Just go to a store and buy some individual bottles. The is a great little store just outside of the Grote Market by the Grand Place.

Try them all! Everyone has different tastes so you will only know what you like by trying them.

Try Chimay, Orval, Westmalle,... wich are all strong 'trapist' beers. If you want something lighter, take Geuze or Kriek, whcih are tipically from Brussels and its region. And sorry Paul, Amstel is from 'Amsterdam', the Netherlands. ;-) Belgians don't like this...