Those scripts work fine for me and many others.
The purpose here is to figure out where the problem is. Once you've identified the problem, then you can fix it, or ask somebody else how to fix it. These are debugging steps only, don't think of them as solutions.
1. Deactivate all your plugins. Really. Refresh your admin pages (ctrl-f5). Refresh your admin pages after every step, in fact, to be sure it's trying anew.
2. Switch to the default theme. Themes can cause issues too, just like plugins.
3. If that doesn't work, clear your browser cache and disable Google Gears (just to be sure that your browser is loading the right stuff).
4. If that still doesn't work, reload ALL the WordPress files onto your server. Make sure that every single file got uploaded correctly.
5. Nothing yet? Try activating the "Use Google Libraries" plugin. This plugin switches many of the JS libraries to load from Google's servers directly and it disables the script concatenation features of WordPress. Often this solves problems. Often it makes sites load much faster, in point of fact, since Google servers are way faster than most things on this planet. If it doesn't work though, disable the plugin again. (Note: If this works, but you don't want to keep this plugin, try adding
define('CONCATENATE_SCRIPTS', false); to your wp-config.php file. That does the same thing, without the benefits of the plugin.)
7. You've verified that you can indeed pull the files, and the error is not showing in the console or it's not an "undefined" type of thing. This probably means your server is blocking AJAX requests. This is almost always mod_security interfering, so disable mod_security in your .htaccess file (Google or your webhost will tell you how).
8. Still nothing? Google for the error messages and see if somebody else has the problem.
9. Last resort, post the errors on these forums, in a new thread. Give the error, give a link to your site, and give a precise description of the exact issue. What specifically does not work? What are you clicking on? Detail matters.