Really, no. But if you know which are windows/mac defaults you can use those. For example, in the css: p {font-family: "Bradley Hand ITC", "Another font", "And another", "some backups ones", Verdana, Arial;}
http://www.ampsoft.net/webdesign-l/WindowsMacFonts.html
For things which must be a unique font you'll have to make an image.
Also, automatically stretching an image for a background often looks poor. A tried and tested solution would be to basically keep it the same but stick it in the middle of the page:
Cliched, sorry, but that's the basic design for a reason. You need to get some ideas together from this chap, work out what you want sort of thing.