Duron to Athlon: can i make the change?????????

i got a 800 duron on my motherboard. i wanna upgrade to a 1.2 or 1.1 athlon, maybe a thunderbird. what exactly would i need to know to do that eg: how do i find out what kind of motherboard i have, and does it support change. lemme give you guys a few more details. Using your vastly superior knowledge of computers and your keen intellect, do you think this would be possible? my computer was a refurb that i got from compaq, before they were bought by hp and started shipping out hp computers in a compaq case. i know my pc was meant to be upgraded, becuase it has a ram capacity of 768 megs, and it is nice and roomy, not hard to get to anything like a lot of hps are, where you have to remove the drive bays just to get to the ram. help me out or at least point me in the right direction, fellows. thanks in advance. PS: i especially need accurate image and Uranium 235's VAST minds and smarts. VAST, right guys?