The My Mood is what you can use to show your mood when you're online. You will see a little smily on the top right hand side of your screen. Click it to change your mood! It is also a handy way while viewing posts (a smily depicting the forumer's mood will apper next to their screen name) to see if that person is online!

As to deleting, you can delete your post within the edit time (6 hrs I think) by clicking the delete post button that will appear when you click edit your post

Have fun!