I wanted to use C2F, but on the website there's a disclaimer at the top >>
Note: Safari 5.1 drops support for WebKit Plugins, which unfortunately includes ClickToFlash.
Try out Marc Hoyois ClickToPlugin Safari Extension.
So...I've been using ClickToPlugin and I have to say I'm very impressed. The preference menu is a bit complicated, but you'll figure it out in a couple of days.
Don't know if you do much YouTube surfing, but if you do you should "opt in" to the html5 trial >>>
http://www.youtube.com/html5. Doing so will let you view videos which are available in html5 format, and if not will revert to the normal Flash player. However, remember that if you enable ClickToPlugin on YouTube, your browser will attempt to use an html5 player for "all" videos.
I actually disabled ClickToPlugin on YouTube since I opted into the html5 trial. Specifically because some of the videos I enjoy watching just load faster using the Flash player. I don't feel the need to block all Flash content on YouTube.
As for the rest of the web, yes ClickToPlugin all the way!