Menu in widget with yahoo style

Check your site source to see what classes do your category links have on them, then style these classes with CSS, like: .category-5 a{ background:transparent url(images/…) no-repeat left top; padding-left: 25px; }

Menu System: Custom Links

sure, just click Screen Option on top, and check Link Target and you will have the option on the link to target the same or a different page