How come when i make a Background its to smalla nd it repeats itself i dont want it to be smalll and centered so it wont cover the page i want it to be big enuf to cover the whole thing.

then make the bg bigger?

i dun understand wat ur tryin to say.. o.O

its called "tiling"
as far as i know theres no way of it not stop happening, unless you make the your bg pic big enough so that it can fit the whole screen. if it don't the where ever theres space to be filled, your bg pic will repeat (tile) its over again.

the only thing that i can think of to help you is to make the picture bigger

I don't know how to make a pic better but I guess u could just browse another background that fits on your xanga?

Open up photoshop and make a new document to about 1024x743 pixels or something and enlarge it..there's really no other way..