kwachon
msn.com has been *glitching* recently. Not just the US one, but also the UK and Netherlands versions. If the problem isn't "constant", then this could be the issue.
Next, type this into the search bar
http://www.msn.com/ , let it load and then save it as a favourite. If it loads in from that favorite it will be ok as your home page. What can happen is that although you have the site saved as "home" it is cached (saved) onto your system. When they change things, then that doesn't work the same as what you have saved isn't the same as what exists.
Because everything else works fine, you are looking at it either being an issue on the msn site or an issue with what you have saved on your PC. Frustrating, I know.... (Oh, UK MSN site is
http://uk.msn.com and works fine over here)