Need help on changing link colour on # respond

1. Try adding:
#respond {color:#fff;}
to the bottom of your stylesheet.

2. Try adding something like:

a#commenttab{
position:relative;
top:20px;
}

to the bottom of your stylesheet. Adjust the top setting to suit.

do i have to change things in the comment template to
move things in the way each comment?

That depends upon your theme. If it doesn’t use <?php wp_list_comments(); ?> in comments.php (and I don’t think yours does) , you should be able to adjust the comment listing directly by editing the code.

Or can i do this in the style? I want to have name and date and so on, on one line beneath the comment text.

That kind of major adjustment isn’t really possible (in any stable way) using CSS. You need to edit the comments listing in comments.php

Is there a point in having a number on each post?

It can be helpful for some people who don’t use a graphical browser. Plus, in your theme, it acts as a placeholder for the comment permalink.