I've always given false info to those, when I bother to fill them out at all. If necessary, I just store this false info along with the password in the encrypted file I keep my passwords in. The security questions they use are often easily guessable (although it seems now they are using somewhat better questions). Nevertheless, my attitude is that I'll just make sure to retain the password.
I get the possible security risk of answering quizzes on places like Facebook, but I've done it a few times because it's fun. It all boils down to passwords being a hassle. Almost anything you do to make dealing with passwords easier makes them less secure, but there's nothing better. The only improvements over passwords come from additional authentication factors, like having to grab a code messaged to your cell-phone, or using one of those little security token devices (or the software equivalent). I don't think anything is going to be replacing passwords any time soon.