Changing a block title per theme or page
Here is a per theme solution.
In your View, under Advanced, click on Theme Information, the following pops up:

Now click on style output, and copy the entire code inside in to a new file in your text/code editor.
In my case it is:
&lt;?php

/**
 * @file
 * Default simple view template to display a list of rows.
 *
 * @ingroup views_templates
 */
?&gt;
&lt;?php if (!empty($title)): ?&gt;
  &lt;h3&gt;&lt;?php print $title; ?&gt;&lt;/h3&gt;
&lt;?php endif; ?&gt;
&lt;?php foreach ($rows as $id =&gt; $row): ?&gt;
  &lt;div&lt;?php if ($classes_array[$id]) { print ' class=&quot;' . $classes_array[$id] .'&quot;';  } ?&gt;&gt;
    &lt;?php print $row; ?&gt;
  &lt;/div&gt;
&lt;?php endforeach; ?&gt;

Change the &lt;h3&gt;&lt;?php print $title; ?&gt;&lt;/h3&gt; to &lt;h3&gt;Your Custom Title&lt;/h3&gt;
Then save the file as views-view-unformated--[view-name]--[machine-name].tpl.php
(In my screenshot, example is the name of my view, and machine name is page, basically use last name suggestion)

Put this template file in your Adminimal theme's template folder and clear the cache to see changes.