I had an IE10 problem related to checkout - maybe the solution will work for you too.
I figured the problem was actually related to Internet Explorer 10 (by the way, I am using Windows 8, but with Classic Shell) as it was working fine in earlier versions of IE, or Chrome or Firefox.
I read several suggestions to force the browser to emulate an earlier version of windows, using something like this…
<meta http-equiv="X-UA-Compatible" content="IE=7" />
which can be put into the Head Section by inserting it in the Admin Panel at System>Design>Miscellaneous Scripts (then flushing Cache). However, this didn’t work for me.
Instead, I found another posting which suggests editing in the .htaccess file. You can achieve the same effect (forcing windows to act like an earlier version) by inserting this code at the end of your .htaccess file…
BrowserMatch MSIE best-standards-support
Header set X-UA-Compatible IE=8 env=best-standards-support
(thanks to Joe Fletcher)
Be aware, it says that you must have Apache Headers module enabled.
Worked for me!