For my sister her website (www.m-am.nl) I had issues with IE8 
Some rendering was not done properly, but it worked fine on IE7...
After some searching, I found the fix. Put the next line direct after <head>:
<meta http-equiv="X-UA-Compatible" content="IE=7" /> <!-- for IE8 Compatibility -->
And IE8 will be forced to become compatible with IE7.
So you have something like this:
<html>
 <head>
   <meta http-equiv="X-UA-Compatible" content="IE=7" /> <!-- for IE8 Compatibility -->
   <title>Foo Bar</title>
 </head>
 <body>
   <!-- website content --/>
 </body>
</html>
