How can i go about this? I would greatly appreciate any expert assistance with this issue, i am trying to find out how but i cant seem to find any way

I have 4 buttons from images i created via Photoshop, now i want to get a drop down kind of popout menu when you go to them just like the ones in http://geeksontime.com/ on the left hand column, rollover "who we are" and youll see the menu and waht im talking about.
My first question is. whats teh best way to go about creating the dropdown/popout menu with links, im told suckerfish menu is the best way so far but im open to any suggestions,...

I have a div container that i have created now i just want to make sure that its horizontally centered in any browser and in any resolution, so that when ever its on 800x600 or 1280x1024 its STILL centered horizontally no matter what, instead of sticking to the left side of the browser window in different res' or window adjusting of any kind.
Thank you kindly