All of the solutions I offered, save perhaps DriveImageXML are going to require a reboot, which you say you don't want to do, so that may limit your choices some.
VMware P2V allows you to migrate a physical machine to a virtual machine. YOu set up a VMWARE server with adequate resources, set up a P2V help VM, reboot your Physical server with the P2V cd, and then use the P2V wizard to clone your physical machine as a VM on your VMWare server.
BartPE is functional Windows XP or 2003 on a CD (thus allowing you to run apps, such as Ghost without instlaling them on the server,but that doen'st meet your no reboot requirement, sorry).