HTML Drop Menu

Hey. i made a drop menu (just like one where you choose you country...) but now i dont know how can i make everythink working. I made it for runescape power lvling service. When i select all requres and i press show items it doesnt happen nothing. I get this drop menu's HTML source code from another runescape power lvling website (rpg stash). pls help

i also uploaded picture and link to website how it should work.
it should work like this: http://runescape.rpgstash.com/skill-leveling/

and code i used for this menu (i removed few options becuse i wont provide them)