How about St.Wolfgang in the Austrian lake district? It will be the end of the ski season in March so still nice and lively but not so cold. It's a large village on a beautiful lake and about 45mins drive away from Salzburg. There's good bus services, lots of excursions, activities in resort and lovely hotels and bars for the evening. The scenery is breath taking and the people wonderful. So long as you're not veggies or teetotal you'd have a lovely time. Going to Salzburg for sightseeing and shopping is great and the culture and history there is fascinating. Plus, if there is a bit of snow left on the slopes (short bus out of town) then you can get a cracking tan on any bits you're brave enough to expose!