1) You just need to go into single.php where you will find this code:
Posted: <?php the_time('F jS, Y') ?><br/>
Categories: <?php the_category(', ') ?><br/>
Tags: <?php the_tags(''); ?><br/>
Comments: <a href="<?php comments_link(); ?>"><?php comments_number('No Comments','1 Comment','% Comments'); ?></a>.
which you can remove (or comment out). You can leave any of them in if you would like.
2) I believe you need to remove this code from page.php:
<a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title_attribute(); ?>">
As well as the
</a> after it.
3) Not sure what you're asking here - you should just be able to delete it as a category while logged into your profile!