When working with ASP.NET you have to remember that all of yoour controls in the end get rendered purely as HTML. In HTML there are no equivalent elements to create a multi-column list or combo box.
I am assuming here that you want to take inout from these controls. However, if you are just wanting to display data in multiple columns then a GridView, DataList or Repeater control may be what you are looking for.
Does this help at all? Or was you question related to something else...?