New edit box when posting

How do you change the back ground colour on the new edit box? with the default font colour you can not see what you are typing! its maddening .  And If I change the font colour with the button it just adds the 'colour =xxx' tag to the start.
Also I can't figure out how to respond to a post by clicking the 'quote' button. When I do I can't add new stuff under the quoted part without it being part of the quote. I have to copy the bit I want to respond to and manually add the 'quote' '/quote' tags in a new post.

Edit: I should add that the text colours are fine if you use the 'quick reply' box at the bottom of a topic, but not when starting a new topic or when editing a previous one

^