Your comments state that the line in question that gives the fatal error causing your white pages is this line:
<div id="whatstrending"><h1><?php echo get_option('radio_options')['blog-header'];?></h1></div>
Or more specifically:
This is invalid PHP up until recently, and your new host doesn't run a version of PHP that supports this.
You can fix it by refactoring it from:
$options = get_option('radio_options');
Rinse repeat in any other situation that follows the same pattern. As a sidenote, the
function()['arrayaccess'] pattern is an anti-pattern, a single line should do a single thing, and calling a function then accessing its return value is 2 things. Not to mention that it will fail if the function doesn't return an array.