Mario Linhart: Here is the place for Outside Events. In the summer concerts, in the winter skating, and the christmasmarket. They're selling sweets, punsch, gluewein, etc. Just go there and Try it !
Hostelling International: For paintings, I enjoyed my visit to "Kunsthistorisches Museum"=lots of paintings from 15th century and later (even the building itself is quite impressive) - Karine (Belgium)
CITY SPOTS WIEN: Ask for CITY SPOTS, the annotated City Map of Vienna (free!). If you like HAUS DES MEERES, then you may like the other recommendations as well.
Marko Kovic: Cool place to visit when you are in Vienna during Summer time. Check Web fo entertainment r program and excellent food opportunities at the Vienna's City Hall park! Highly recommended.