Is there an option to disable all javascript?
How can I make the captcha always appear on the login page even when it's their first attempt logging in?
there is no option to disable javascript and many features of forum will not function if javascript is disabled.
login form doesn't has captcha for normal login. captcha can be shown for failed login attempts
Login Captcha Protect plugin may be tried by
changing compatibility
I just want to point out that captchas are not as good as they once were. They are more of an annoyance because of how difficult they can be for legitimate users to read. You're better off using a question at registration which is a built in feature, however, I recommend deleting the default questions and coming up with ones users that come to your forum should know.