If being able to do things with off-the-shelf tools is important, I'd recommend PBKDF2. It can be implemented in a couple dozen lines of code over one of the SHA2 functions, as opposed to Bcrypt which is a completely novel hash function that isn't in most languages' standard libraries.

Much as I like bcrypt/scrypt, I generally just recommend PBKDF2 with a large number of rounds. It's not perfect, but it's more than good enough.