re: Salzburg questions - day trip

Yes, probably a 15-20 minute walk, depending on how fast you walk.

The area leading up to, and immediately around the fortress is really nice.

You can grab a bosna at Balkan grill for a quick snack.

The Augustiner beer garden was a lot to take in the first time. It opens at 3, and will probably have a large line/crowd waiting to get in if the weather is nice. From there it was kind of a mad dash to get a table and in line for beer. They serve one beer, their marzen. Order a full or half liter from the cashier, save the small receipt (very important), grab a mug from the wall, wash it out, then hand your small receipt and mug to the guy pouring beer, and that's about it.

The food hall is pretty big there, I had the leberkase, very good.

If you're a Mozart fan, you can see is birthplace and childhood home.