First of all, we do not include non-secure algorithms to our software.
Regarding the strength of protection, if we consider brute force attack on the encryption key, only length of encryption key is of importance.
From that point of view , Blowfish-448 is preferable.
If we consider performance, RC6 is the fastest algorithm in BestCrypt implementation.
We may consider Rijndael (AES) as an algorithm, which was more extensively evaluated than other algorithms - and this fact is very positive when we speak about security of an algorithm.
If you wish, refer to the article of computer security expert Bruce Schneier: Can the NSA Break AES?
The newest algorithm implemented in BestCrypt is Japanese cipher Camellia.
Take a look at the BestCrypt help chapter to know more about the algorithms, their specifications and history of creation:
Additionally, you should use XTS encryption mode and KG-Ghost key generator for the strong protection.
Finally, take into account that quality (i.e. length as well as complexity) of your password is of great importance, much more than encryption algorithm.