Minis should be at least a foot from the wall, a bit more might be better, but it kind of depends on the room, how picky you are and how much room you have. Expensive stands don't actually improve sound, but
good stands that are solid and stable are definitely worth your time. Check out the medium mass stands
here. I've owned them and they are quite solid for the price. They don't look that impressive in the pictures, but they are better than anything else I've seen for $60/pr. I also have the High Mass versions, which would be a bit of overkill for the Minis, but they are also very good for the price.