Topic: Change Backround image

1.How to change Backround image  in defult Oxygen theme like i ilustrate on this pic below.
Lines presents image backround.

http://img440.imageshack.us/img440/8576/save1k.jpg


2. How to set up to be defoult outzoom theme like in my picture. I dont want this defalut zoomed theme. Do I need to change margines on theme or...?