I have seen problems similar to what you are describing in the preview. The issue in these cases was the version of IE that was installed, do you have IE6 installed? On my test environment with IE 6 I get the same result.
If you do have IE6 installed you should try upgrading the browser, I would suggest going with the new IE8, it seems to work well.
If you do not have IE6 installed please let me know and also tell us what IE you do have installed and when you updated it.