It seems like you can create a title for every post, but the overall category pages, and the index page will not have a title. Can you put in an if..then..else statement that would display the custom field "title" if it exisits for that page, or if not, default to the standard title and post date?
I don't know php, but it seems it would be something like:
\
<title>
<?php
if (!empty "title")
{
?>
<?php echo wp_title() && " " && the_time('l, F jS, Y') ?>
}
<?php
} else {
?>
<?php echo title() ?>
</title>
\
I know the syntax is way off, but then again I told you I don't know PHP.