WOW! If you want stay in Vienna, with walking distance to the city, in a quiet environment but with still have enough options for dinner, please stop looking and stay with Gerrit! Lovely place, with a big living room and big sleeping room. The shower/bathroom was a little smaller than usually, but still large enough to 'do your thing'. It also included a washing machine (but didn't use it).
Gerrit was very fast in replying and helping to give the best directions to his place, which is also very near to the subway.
I would definitely try to book this place again when I travel to Vienna.