It's quite difficult to explain which kind of city is Brussel... because it's really different from the other belgian cities. Not only is the biggest city, it's also the political and cultural centre, a risky mix of cultures, you can get lost in its streets and then feel like far away... but I think that if walloon and flemish struggle for it, they must have good reasons.
Normally most visitors arrive at Gare Central or Brussel Centraal, the main train station. If you come by train to Brussel, the international station is called Gare du Midi or Brussel Zuid. The city centre includes different ways of life, there is not only the most known buildings or museums, there are some other interesting and not really turistic places. It's only up to you if you want to get lost inside the old Brussel, sometimes it can be a bit creepy in the evening but I find it really cool because of the amounts of people who is going and coming anytime. I'm sure I should write different posts about Brussel, maybe the best start is going for a tour around the old town.
For the time being, I've been there four or five times so I'm not really an expert but I think it's so nice. When you're off the train in Brussel Central and you go outside, there's a square with the Le Meridien Brussels Hotel. You cannot really feel that you're in Brussel until you go a bit far through the Madelein street and you can smell the fries. In the corner between that street and le Place the Spagne there's one of the typical fries take-away shop. It has been the best one as far as I can know, and you can buy fries with different types of sauce, I've just discovered the brazilian sauce and it tastes really good! It's quite sweet but you can also find spicy ones.
Normally there's a market in the square where you can find atypical souvenirs like beer shaped candles or handmade t-shirts. Not so far there's the Galerie de la Reine, one of the beautiful places of the city centre where you can eat something or buy chocolates. But if you just follow the smell of chocolate you'll go to the Heuvelstraat, a small street that leads you to the famous Grand Place. There it's so funny to go inside the chocolateries and really get excited with the big chocolate fountain, if you're lucky someone can invite you to try it for free! it tastes really good and not too sweet. It's an important street also because of the Tintin Boutique, a nice shop about the famous cartoon plenty of t-shirts, teddies and so many things.
When you just follow the people and go to the Grand Place you can realize you're in Brussels. I don't know really why. You get really impressed for the beautiful buildings but also because there's a lot of people there and it's really a nice place to take pictures. Depending on the day you go to the Grand Place you can find a flower markt and a lot of painters selling their art. While you're looking around it, you can see that each building has its own charm... it's not just the appearence, it's also the story that all of them hide. Some weeks ago I went to Brussel and there was a big beer festival with a lot of tents selling cheap beer and people just staying there enjoying the sunny day (www.weekenddelabiere.be)
When you know the story about the Brussels City Hall you feel a bit skeptic because it's funny and sad, maybe because the city can also be funny and sad. The city centre is plenty of street sellers trying to give you roses, cleenex or whatever they have... and there are also a lot of beggars (as probably in all the big cities). It makes you feel a bit strange because you are really enjoying the city as a visitor but probably everything changes a lot when you are in the same street every day. Following the Rue de l'Etuve you'll be in one of the souvenir streets, but I don't really like this kind of typical presents. If you want to find better designs you have to go to the Brussels Corner shop in this street and also in Grasmarkstraat (close to the Galerie de la Reine). The most interesting shops in Rue de l'Etuve are the laces shops and the typical chocolateries. But if you feel really sweet and you want to see the Manneken Pis, the famous statue, you just have to follow the belgian waffle smell through the street.
The Manneken Pis is smaller than you think, sure. But it's also sorrounded by tourists. The funniest thing is visit him different days and see how many dresses he has. Sometimes it can be a bit stupid but the legends around the statue are funny. There's also the Manneken Pis Chocolaterie with a lot of different products inspired in the famous statue. The fist time I saw the Manneken Pis I couldn't find anything such interesting to be as famous as he is. And five years ago I cannot really find it cool. But it's different... and Brussels is different.