1. Use <h2> text </h2>. It should work. If it doesnt work, then open "style.css" file and add following line in h2{} section:
Code:
border-bottom: 1px #000 solid;
You can add the above code in any other heading section, like <h1>, etc, then use the same heading for your titles.
2. Use <blockquote> text </blockquote>. You can customize the background color, border, text color using "style.css" file of your theme.
3. No idea.