i don't think there is a "best school" out there.. I can tell you that some schools are good but not best..next person that writes an answer to you can say that instead of the schools i named "b" and "c" are better.. and so on..
distance learning is going to depend quite much in YOU, your discipline, time, effort.. The school will just give you feedback when you need it or either the students in the forums will do..
You have probably heard about Oxford Aviation Training, Bristol, Cabair,FTE...etc.
The best thing you can do is check directly with the schools and see what they offer you.
Good luck with your studies!