Personally i found upgrading using the command line, much easier and much more informative than using the WFE.
I found that the best way to perform an upgrade was using simple PHP commands.
- Load an Administrative Command Prompt.
- type the command shown below.
- Next you will be asked if you want to proceed with the upgrade.
- Type "Y" for yes and hit Enter.
== Upgrading Moodle database from version 2.5.2 (Build: 20130909) (2013051402) t o 2.6.1+ (Build: 20140213) (2013111801.08) == Your Moodle files have been changed, and you are about to automatically upgrade your server to this version: 2.6.1+ (BUILD: 20140213) (2013111801.08) Once you do this you can not go back again. Please note that this process can take a long time. Are you sure you want to upgrade this server to this version? type y (means yes) or n (means no) :y
Now wait for it to complete, this can take a while.