I have had to edit this question because it was too broad (sorry didn't realise that was not allowed...), so, lets go with:
Is AES256 the most secure encryption algorithm available at the moment? If not what would be a more suitable alternative?
It would be great to see a comparison table for various encryption algorithms if one exists. If the benefits are comparable.
Not sure why I'm being down voted so bad, thought I asked a reasonable question?
Looking at TLS is a good start, there's different problems solved by different algorithms. These are considered secure enough, the brute forcing of large enough keys becomes impracticable this answer has the whole "how strong in terms of millions of years" answer.
For protection against quantum attacks this answer is a good overview, for example the theory right now is for symmetric encryption you just double the key size and your are good to go. Quantum computers can be a concern in the future, but the biggest number arguably factorized so far is 16 bits, until they can do the x bits used in an RSA implementation there isn't much worry.
Of course if you want the most secure you should use a key as big as the message (a one time pad), as this provides perfect secrecy in a method that is simple to implement and understand. This has been known since at least the 1940s.
