You'll actually need to use CSS to do those things. Here's how they work. :)
Background:
body{background:url(imageurlhere) backgroundcolorhere;}
You have to fill in the red spaces. Use the image url (the direct link from a site like Photobucket) where the first red text is. If you do this, generally you can just put "transparent" where the second red text is. If not, and you want a solid background, or a background to fill in leftover space, type in either a common color, like "red", or use hex codes. You can use Google to find a nice list of them.
Text Color:
div.box{color:color;}
Once again, you're substituting either a common color or a hex code.
Change the color behind:
div.box div.body{background-color:color; background-image:none;}
Here's the important part. All three of these have to go inside style tags. That means that you put <style> at the beginning and </style> at the end.
Let me know if you have any problems getting this to work!