Yes, you can install Nova on physical machine running Ubuntu 10.04. Make sure a hypervisor is running in your machine. Ex: KVM. A supported hypervisor is required by nova-compute. You might want to refer to hypervisor support matrix here http://wiki.openstack.org/HypervisorSupportMatrix (http://wiki.openstack.org/HypervisorS...)

Hope that helps!

Also you can find install guide here http://docs.openstack.org/diablo/openstack-compute/install/content/index.html (http://docs.openstack.org/diablo/open...) starter guide at http://docs.openstack.org/diablo/openstack-compute/starter/content/ (http://docs.openstack.org/diablo/open...)