Removing Tittle from node based posts and change for category

sorry for post this.. but i need help urgent pleaseeee… I need to change the CODE, This Code displays the date and the number of comments and I need to change to display the date and category, i need chabge only numbers of comments for category, I use the Arras theme ..

if ($show_meta) {
		$postheader .= '<span class="entry-meta"><span class="entry-comments">' . get_the_title()  . '</abbr></span>';
		$postheader .= '<abbr class="published" title="' . get_the_time('c') . '">' . get_the_time( get_option('date_format') ) . '</abbr></span>';
	}

and change get_the_title and show category.

Please someone can help me. thanks in Advanced