Misty 3.7.1 on wordpress 2.7

I want to allow a larger image to be displayed on my blog
I know some HTML 4.01 Transitional and Strict.
How can I change the about of space the header image uses, using css or html or xhtml?

Please help

blog: cuisinecitrine.com/wordpress
how can i also change the url, I bought the name cuisinecitrine.com,
but my current url has /wordpress after the .com, how can I use the url I registered?

And How can I change the color of the text to hot pink?

THANKS EVERYONE!
PLEASE HELP!!