Frau A and I went to Vienna in February. It's just far enough to feel like you've escaped, but the trip is not too taxing. Around 4 hours by car, a little more by train... you could fly from Munich (less than an hour in the air) but the trips to the airport are almost not worth it.
During our weekend in Vienna, Frau A and I took the city "circle" tour on a bus. It's cliched, but actually a great way to quickly get oriented in a new city, and to see some of the interesting sites (and then decide which ones to see in detail the following day).
We boarded a train from the stop near the hotel, and headed towards the inner city. Some trams look more modern than the ones in Munich, and almost have the curves of, dare I say it, a ski gondola. It is Austria after all.
We arrived near the Opera Haus, from where the buses depart. This is one of the largest Opera Houses in Europe, completed in 1869 and then rebuilt from the original neo-renaissance plans after the World War II.
It wasn't originally very popular with the Viennese -- the initial reception was so bad that one of the two architects comitted suicide, and the other suffered a fatal heart attack (Wikipedia always has the good news for me). Nevertheless, they did decide to restore it like the original (with just a little modernization), and it's an accepted part of the city today.
Unfortunately, because it was winter, the fountain on the side of the Opera Haus was boarded up. (All the ones in Munich are, too.) But it still is a common place for people to gather, and for the companies to sell tour and concert tickets to tourists. We didn't capture them on film, but guys in traditional outfits roam this sidewalk accosting tourists, trying to sell event tickets.
One of the downsides to a bus tour is that it's not a great environment for photography. The bus windows are pretty clean, but there is always a little grime on them. Plus there are glare & reflections to deal with. (Murphy's law: when there's something interesting to film, the bus is moving and you're getting jolted around....when you're stopped at a red light, it's in front of McDonald's.)
We did get a few photos that are share-worthy... The one below is the St. Francis of Assisi Church, also known as the Jubilee church (celebrating the reign of Emperor Franz Josef). Unusually, it is located outside of the old city and close to the modern quarter.
We were then driven by the Austrian Parlaiment building, and decided to come back later on foot. The streetcar/tram lines obstruct the view a bit, but you can definitely see the greek-style columns -- it was designed this way to reinforce the idea of democracy (completed in 1883). The two houses sit here, and it's quite practical: the Austrians include meeting lobbies, a gym, and of course multiple bars for their representatives.
Still on foot now, we're heading towards the Rathaus from the Parliament. You'll see a lot of horse and buggy tours in Vienna, and it's easy to understand the romantic appeal. The fence here surrounds the grounds to the Hofburg Palace, which we did not get a nice photo of... the bus didn't work for us and we didn't have a chance to walk by again later. Ugh! Check the link to Wikipedia or Google images, it's really quite impressive.
Finally we arrive at the Rathaus. The building is so large that we tried my new wide-angle lens and had to keep it at the widest setting: 18mm! Completed in 1833 in gothic style, the Rathaus seats the Burgermeister (mayor) and city council. It has a pretty nice restaurant too, serving traditional Viennese food. The park in front has events year round, and hosted the Vienna Ice Dream when we were there -- a blog post unto itself!
Overall, we definitely recommend taking the bus tour around the city, then pick your spots to come back to. You'll need more than a weekend for Vienna, but it's a start.
