Javascript error in Blog Types plugin

Blog types seems to load some of it's javascript all the time (setup_subtypes_box() is attached to the wp_head action). The problem is that this javascript has a function called setup_subtypes_box() that does this:

var types_box = document.getElementById('blog_type');
var types_box_value = types_box.options[types_box.selectedIndex].value;

Since the element with the id 'blog_type' does not alway exist, one of two things needs to happen:
1) Conditionally load the javascript only if the element it written out (this would be best)
2) Adjust the code to avoid the error like this:

var types_box = document.getElementById('blog_type');
if ( ! types_box ) {
return;
}
var types_box_value = types_box.options[types_box.selectedIndex].value;