1 + 2 have been answered
3. You can do ATPL theory with any school, and CPL + MEIR with any school. The benefit of staying with the same school is that you may well get a better relationship with the school, and they will get to know your strengths and weaknesses. But you don't have to it all with the same FTO.
4. Whatever is best for you. Some people prefer all software (not me), others prefer books (me). Some like distance learning, others full time residential courses. Only you know what is best for yourself.
5. I've just started with Bristol and am impressed so far. I think they have software for Ipad.