Don't use myspace

But seriously, i know myspace allows you to use html in your about me box, so theoretically you could open a <head> tag and throw a javascript code in there to disable right click, but that could screw with the layout of the page, since you'd be opening a <head> within the <body> of the page.

If you can upload a file, you could upload a .htaccess and do it that way. But no matter what you do they can always print screen. Your better option would be to watermark your images so when they're taken, it's just advertising you.