Do you really need 250 GB for the VM Hypervisor? VMWare ESX will boot
off a USB flash drive. If you're using Linux KVM you would ideally
want to have a minimalistic install anyway. A good Linux console only
live distro doesn't even fill a single 700 MB CD. Unless you're doing
something else on your VM host I would give it a small system
partition. Limited space keeps temptation at bay.

Personally I like things as simple as possible and would most likely
just do one big volume. If you wanted to future proof the installation
you could setup LVM so you can easily add disks/storage to your server
down the road (via external array, JBOD enclosure, NAS, SAN,
whatever), but my experience has been that we end up justifying the
new servers and storage and end up doing new installs on the new
hardware anyway, so the benefits of LVM don't end up justifying the
extra complexity. YMMV of course.

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
IT Outhouse Blog Thing | http://www.itouthouse.com