When to use --hvm / --paravirt / --virt-type options with virt-install in KVM?

Issue

"man virt-install"
       -v, --hvm
         Request the use of full virtualization, if both para & full virtualization are available on the host. This parameter may not be
         available if connecting to a Xen hypervisor on a machine without hardware virtualization support. This parameter is implied if
         connecting to a QEMU based hypervisor.

       -p, --paravirt
         This guest should be a paravirtualized guest. If the host supports both para & full virtualization, and neither this parameter nor
         the "--hvm" are specified, this will be assumed.

       --virt-type
         The hypervisor to install on. Example choices are kvm, qemu, xen, or kqemu.  Availabile options are listed via ’virsh capabilities’
         in the <domain> tags.

• Does this mean, that KVM can be used on hardware without AMD-V or VT? And if so, what argument should be used?
• If the hardware have AMD-V or VT, what argument should be used? -hvm or --paravirt ?
• Is it correct understood that, use --virt-type=kvm for RHEL, and --virt-type=qemu for Windows? If that's correct, when is kqemu used?
• Which  is recommend for RHEL54 and RHEL55 guests?