The iso downloaded from the main site ships with kernel 3.2.0-51-generic as can be seen in the picture below when running the command uname -r in terminal :
You might have problems booting and installing elementary OS with newer hardware. In this case you can download an upgraded iso with a newer kernel from this page : http://sourceforge.net/projects/elementaryos/files/unstable/ .
Choose elementaryos-unstable-amd64.20140331.iso or elementaryos-unstable-i386.20140331.iso according to your architecture ( unstable here just means updated ).
Kernel version : 3.11.0-19-generic ( date : 2014-04-01 ).
Elementary OS is based on Ubuntu 12.0.4 LTS ( Long Time Support ). In order to support a wider variety of hardware Ubuntu releases so called Point Releases ( 12.0.4.x ) with an updated kernel, X.Org-Stack and Mesa ( see : LTS Enablement Stacks ). Latest version is 22.214.171.124.
In case you run elementary OS with kernel 3.2 successfully and think about upgrading to a newer kernel, you should read this article first : http://shnatsel.blogspot.com.es/2013/12/why-you-should-not-upgrade-kernel-on.html