Did you realize the possibility of running e.g. IE6 and IE7 together? - I didn't till today...
I had installed IE7 Beta2 when I realized, that I can't work on Gadgets for Live.com with IE7 on my development-server because of security limitation (do not allow cross-domain XmlHttp requests from trusted sites). - So I started to google, and found a solution which works for me: I installed IE7 stand-alone with some limitation - but still okay for me.... read the following articles for more information: