How to force certain sections of the website to be browsed under SSL?

On our website certain sections or pages deal with sensitive user or account information. I want to force the users to browse those pages under HTTPS. Whereas other pages with public content should be available under HTTP. I was planning to install url Rewrite module on IIS and write rules to achieve this. I am not sure how to write the rules in web.config for redirection.

3 requests for every resource (2 x 401.2 and 1 x 200) in a windows authenticated asp.net mvc app

I was trying to track down why my site was so painfully slow in IE9 when I pulled out Fiddler and realised that every request is being sent 3 times (twice I get 401.2 and then a success). I verified this happens on all browsers, its just that Chrome’s speed was masking this (or it could be that this has nothing to do with my sites performance issues in IE).