Sorry, forgot the Wien-Salzburg question.
Depending on the train type, direct (no change of trains needed) take from 2 hrs 45 minutes to 3 hrs 20 minutes.
One-way fares are about €57,- in 1.class or €37,- in 2.class
Keep in mind that trains for Salzburg depart from and arrive at the WESTBAHNHOF, rather than the SUDBAHNHOF.
Here is the english version of the OBB website, where you can check schedules and fares:
http://www.oebb.at/en/index.html