In case you don't know how to create menus with CSS (or just don't want to), you can use izzymenu online menu builder. Here is a short screenshot-description of what you can do:
Step 1 - Chose general menu styles: colors, backgrounds and dimensions
Step 2 - Chose link styles: colors, background, borders and sliding door images. If you don't know what sliding doors technique is, read my previous blog on this subject.
Step 3 - Chose hover styles
And the final result will look like the sample below. In addition to this, you can chose menu and submenu items, you can save your result online, or you can browse menu gallery.
Again, izzymenu URL is www.izzymenu.com.