Vcenter upgrade from 2.5-4.1 and move to new host

Hi all. Sorry for my ignorance but I am completely new to vmware. I have picked up a client who curently has ESX 3.5 and Vcenter 2.5 running on server 2003. I would like to move to a new server 2008 host and upgrade to Vcenter 4.1. I have read some suggestions that a clean install would be better vs an upgrade. I am really just looking for the fastest solution that will allow me to manage the VM's from the new 2008 host with vCenter 4.1. Please give me some guidance (possibly hand holding ) on this process. Thanks!