I\'ve just setup my EC2 server following this video here exactly - http://www.youtube.com/watch?v=bBajLxeKqoY
I even chose the same server type, everything went well
If you need to do things as root once you are in as ec2-user, use sudo su - that gets you to root and doesn't need a password. Somethings you do need that for, like looking at the tomcat log files
sudo su