If you have an image that small, you really shouldn't be stretching it to fill the entire page, just image how horrible a 280x177 image will look on an average laptop at 1366x768 or even on some machines at 2560x1440 -You'll be able to see the individual pixels!
If you really want to do this bearing in mind how bad it will look, you can use the CSS3 background-size property:
http://www.w3schools.com/cssref/tryit.asp?filename=trycss3_background-size2.
Nowadays you should be using CSS for all of your styling, using inline tags like '<body background="foobar.jpg">', '<font face="verdana" color="green">' and '<p align="center">' is very old fashioned and considered old practice, not to mention the very limited control it gives you over your styling.
