The preferences page allows you to change some account information.

As soon as you enter holiday mode, you will be logged out of your account, and will not be allowed to log back in for at least 75 ticks. You can remain in holiday mode for as long as you wish, and whilst in holiday mode you will recieve no income, and you cannot be attacked by other players.

If you wish to flee your current country, you can migrate, which involves you losing half your units, and half of each resource. You will then be moved to the furthest out country on the map. You cannot migrate if enemy armies are already stationed at your kingdom, or are currently marching towards your kingdom.

Change password
Changing your password you something easier for you to remember than your automatically created password is a good idea, but be sure to make it something difficult for others to guess. Something of moderate length including both letters and numbers is recommended.