Personally I prefer
Gnu Privacy Guard. The source code is open for computer nerds to pick apart. I am not sure how good or easy it is for Windows users. YMMV, but I don't have to say that here, right?

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.0.7 (GNU/Linux)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=MRAe
-----END PGP PUBLIC KEY BLOCK-----