help!

Ok, I am pretty much done, but I still can not figure out how to make my banner fit the space it is sposed to fit. It should fit over the body of the blog (not the side bar) and go clear to the bottom of the frame it is in. Anybody got any ideas?
The banner is a jpeg and I used Picasa/Hello to post it. Maybe ther is no way I CAN fix it. I might as well leave it alone, by the time I get it fixed, it will be December and time to change it again!

Today I had a rare treat. I heard a putt-putt-putt and knew it was a quail, so I looked out the window, and saw not only George and Gracie back again, but their entire spring hatch too! All grown up and pairing off. There were 16 in all. They scratched under the feeder eating the tons of bugs that are living there, then Tilly and Sadie decided to sit in the window, and scare them all off. I also had Alvin the chipmunk from early summer, and 2 lolas and two Suzie's!! It has been a dreary wet dark foggy day, no sun, and I think the critters thought that winter was here and were stocking up!!