1. You need to use starchy potatoes for hash browns as they breakdown when cooked, becoming nice and fluffy on the inside and golden and crunchy on the outside. The best to use are Russet (common in the US), dutch creams, King Edwards or red delight. However, great all rounders like golden delight, coliban, red rascal and Sebago (popular in Australia) still works great.
I use Sebago which are the brushed potatoes you can get from any supermarket in Australia (ie. the ones with dirt on them). If you are based in the US, a great all rounder to use is Russet which I understand is one of the most widely used potatoes in the US.
2. You can make these a few hours in advance, then reheat them in the oven to make them crispy again. They can also be frozen after baking. To reheat, allow to thaw, then pop in the oven at 180C/300F for 15 minutes until crispy and heated through.
3. Nutrition per serving.