For Chrome, go to advanced settings -> Privacy -> Content settings -> Plug-ins and select "click to play". For Firefox, go to about:config and enable "plugins.click_to_play".
For Chrome, go to advanced settings -> Privacy -> Content settings -> Plug-ins and select "click to play". For Firefox, go to about:config and enable "plugins.click_to_play".
I just want to point out that's there's a big difference between having an interpreter on your machine like python, ruby, or java, and having a browser plugin that executes remote code by default.
There's nothing wrong with the former, there's everything wrong with the latter.
(Yes, non-executable data can still deliver a malicious payload, e.g. http://technet.microsoft.com/en-us/security/bulletin/ms04-02.... It's just much less common-- presumably because it's a much smaller attack surface.)
But mostly it is buffer overflow bugs that get you now.
I keep Java around for some other reasons, so when I update, I have to remember to go and disable the browser plugins once again.
Your point is correct, though. There are a lot of sites that break if they don't detect Flash right at page load.
Also on OS X the Flash mouse capture is broken if you enable click to play in Firefox.
I had to go back to enabling plug-ins with Chrome, though, as I couldn't load videos for some reason.