in reply to Choice of encryption modules...

You can't go wrong using AES. It is standard, well-designed, analyzed by experts. It is fast and secure.

Crypt::CipherSaber is a stream cipher based on RC4. RC4 has some vulnerabilities. Also, it is easy to misuse stream cipher and lose the security; this is what happened with the design of WEP. The advantage is that it is fast, simple, and implemented in Perl.

Crypt::Rijndael is an XS implementation and should really fast. Crypt::Rijndael_PP is a pure Perl implementation but it is supposed to be slow. If you can install XS modules, I would go with Crypt::Rijndael and not worry about the security.