Ok, now that ubuntu is installed, ( I assume you followed the directions in the installer so it is installed correctly) you can customize it. You can modify the bars, make them look good, install themes or anything. To install a theme, go to
http://www.gnome-look.org/ or any other site, and download a theme to your desktop, and drag it into the theme section in appearance. (System, preferences, appearance). Themes are the GTK 2.X tap on the side of the website, but i prefer to use the metacity themes because they only modify around the window.