If it's even possible, first you'd need to boot up to where you can load the DVD over the network. Depending on what you have on the target computer, you could use a small or compressed Linux distro on USB key or CDROM like DSL or Knoppix. Then NFS mount the DVD (which you've NFS shared already), locate the installer program, and run it. If the target's BIOS offers PXE boot, you could set up a PXE server for the initial boot. It will likely turn out to be a challenge no matter how you do it. Why not use a USB DVD drive? I see used drives for under $30 on Amazon:
http://www.amazon.com/Targus-PADVD01.../dp/B0000E2Y8N
