Hi,
Server 500 error is a generic error message, it does not point to any code or file.
Your web hosting company should at least tell you what is causing this issue. I think most probably is a plugin conflict or PHP memory exhaust.
You can follow this troubleshooting guide.
http://www.wpbeginner.com/wp-tutorials/how-to-fix-the-internal-server-error-in-wordpress/
By the way, this is not a Theme issue.
I am running version 3.5.0 on my localhost without any problem.
http://i.imgur.com/fii0Jbw.png
Thank you