banner w/drop-down to go to different URLs?

Hi - can anyone help me? I'm trying top figure out how to create a banner (i.e. 468x60) that has a drop-down ('ComboBox' ???) that has, say, 3-4 selections, and when the viewer selects one of the options, it opens up a new window to a URL specific to that selection (in the drop-down list).

For instance, the banner would say "make your selection," and underneath, there's a drop-down list that has the options: apples, oranges, bananas, and pears. When they select apples (then hit a "go" button, or maybe just double-click the selection in the list), a web page pops up that is about apples - if they instead select oranges, a different page pops up about oranges - make sense?

Can anyone let me know how to do this? I've been trying to look it up for days and can't find the answer...