If I were to choose, my preference would always lean towards setting the X-UA-Compatible value to IE=edge,chrome=1.
By opting for this configuration, you ensure that your website will always utilize the latest rendering engine in Internet Explorer, thereby safeguarding its compatibility with future updates.
In case you encounter any issues with IE8, consider implementing modernizr and/or polyfills to address them. Further details on these solutions can be found through a quick search online.
There are multiple factors to consider in finding the best solution for your specific situation:
- Browser behavior may vary between displaying local files (protocol file://) versus web server documents (protocol http://)
- Check if the default X-UA-Compatible setting is specified as an HTTP header on your webserver (you can inspect this using tools like Firefox Firebug's Net tab)
- Determine if Compatibility mode is causing problems by looking for the torn apart page symbol in the address field of IE8/9 (more information available at: )
If none of the above apply, it might be a CSS-related issue that needs attention.