You can add the CSS for formatting those fields right into your website CSS file.
<link rel="stylesheet" href="/store/SLS.css" type="text/css">
It doesn't look like you have any classes specified in your table for the search form. I would suggest adding classes to the cells, <td>, then using your CSS file to add styles to those specific cells. You could try copying and pasting the search table from the following cookbook page:
http://www.shopsite.com/templates/cookb ... form.shtml
For your second question, adding the DOCTYPE tag in your custom search template might fix this issue.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">